var log = new Log('fuse.less');

var quit = function () {
};

function readFile(name) {
    var f;
    if (name.lastIndexOf('/{', 0) === 0) {
        var unitEndPos = name.indexOf('}');
        var unit = name.substring(2, unitEndPos);
        var lessFile = name.substring(unitEndPos + 1);
        f = fuse.getFile(unit, '/public/less' + lessFile);
    } else {
        var pathInfo = fuse.toRelativePath(name);
        f = fuse.getFile(pathInfo.unit, pathInfo.path);
    }
    log.debug('[' + requestId + '] opening less file : "' + f.getPath() + '"');
    f.open('r');
    return f.readAll();
}
/* Less.js v1.7.5 RHINO | Copyright (c) 2009-2014, Alexis Sellier <self@cloudhead.net> */

//
// Stub out `require` in rhino
//
function require(arg) {
    var split = arg.split('/');
    var resultModule = split.length == 1 ? less.modules[split[0]] : less[split[1]];
    if (!resultModule) {
        throw {message: "Cannot find module '" + arg + "'"};
    }
    return resultModule;
}


if (typeof(window) === 'undefined') {
    less = {}
}
else {
    less = window.less = {}
}
tree = less.tree = {};
less.mode = 'rhino';

(function () {

    console = function () {
        function doLog(out) {
            return function (a) {
                //TODO: for some reason loging dosn't work,fix later
            }
        }

        return {
            log: doLog(log.info),
            info: doLog(log.info),
            error: doLog(log.error),
            warn: doLog(log.warn)
        };
    }();

    less.modules = {};

    less.modules.path = {
        join: function () {
            var parts = [];
            for (i in arguments) {
                parts = parts.concat(arguments[i].split(/\/|\\/));
            }
            var result = [];
            for (i in parts) {
                var part = parts[i];
                if (part === '..' && result.length > 0 && result[result.length - 1] !== '..') {
                    result.pop();
                } else if (part === '' && result.length > 0) {
                    // skip
                } else if (part !== '.') {
                    if (part.slice(-1) === '\\' || part.slice(-1) === '/') {
                        part = part.slice(0, -1);
                    }
                    result.push(part);
                }
            }
            return result.join('/');
        },
        dirname: function (p) {
            var path = p.split('/');
            path.pop();
            return path.join('/');
        },
        basename: function (p, ext) {
            var base = p.split('/').pop();
            if (ext) {
                var index = base.lastIndexOf(ext);
                if (base.length === index + ext.length) {
                    base = base.substr(0, index);
                }
            }
            return base;
        },
        extname: function (p) {
            var index = p.lastIndexOf('.');
            return index > 0 ? p.substring(index) : '';
        }
    };

    less.modules.fs = {
        readFileSync: function (name) {
            // read a file into a byte array
            var file = new java.io.File(name);
            new Log('xxxxxxxx').info(file.getCanonicalPath());
            var stream = new java.io.FileInputStream(file);
            var buffer = [];
            var c;
            while ((c = stream.read()) != -1) {
                buffer.push(c);
            }
            stream.close();
            return {
                length: buffer.length,
                toString: function (enc) {
                    if (enc === 'base64') {
                        return encodeBase64Bytes(buffer);
                    } else if (enc) {
                        return java.lang.String["(byte[],java.lang.String)"](buffer, enc);
                    } else {
                        return java.lang.String["(byte[])"](buffer);
                    }
                }
            };
        }
    };

    less.encoder = {
        encodeBase64: function (str) {
            return encodeBase64String(str);
        }
    };

    // ---------------------------------------------------------------------------------------------
    // private helper functions
    // ---------------------------------------------------------------------------------------------

    function encodeBase64Bytes(bytes) {
        // requires at least a JRE Platform 6 (or JAXB 1.0 on the classpath)
        return javax.xml.bind.DatatypeConverter.printBase64Binary(bytes)
    }

    function encodeBase64String(str) {
        return encodeBase64Bytes(new java.lang.String(str).getBytes());
    }

})();

var less, tree;

// Node.js does not have a header file added which defines less
if (less === undefined) {
    less = exports;
    tree = require('./tree');
    less.mode = 'node';
}
//
// less.js - parser
//
//    A relatively straight-forward predictive parser.
//    There is no tokenization/lexing stage, the input is parsed
//    in one sweep.
//
//    To make the parser fast enough to run in the browser, several
//    optimization had to be made:
//
//    - Matching and slicing on a huge input is often cause of slowdowns.
//      The solution is to chunkify the input into smaller strings.
//      The chunks are stored in the `chunks` var,
//      `j` holds the current chunk index, and `currentPos` holds
//      the index of the current chunk in relation to `input`.
//      This gives us an almost 4x speed-up.
//
//    - In many cases, we don't need to match individual tokens;
//      for example, if a value doesn't hold any variables, operations
//      or dynamic references, the parser can effectively 'skip' it,
//      treating it as a literal.
//      An example would be '1px solid #000' - which evaluates to itself,
//      we don't need to know what the individual components are.
//      The drawback, of course is that you don't get the benefits of
//      syntax-checking on the CSS. This gives us a 50% speed-up in the parser,
//      and a smaller speed-up in the code-gen.
//
//
//    Token matching is done with the `$` function, which either takes
//    a terminal string or regexp, or a non-terminal function to call.
//    It also takes care of moving all the indices forwards.
//
//
less.Parser = function Parser(env) {
    var input,       // LeSS input string
        i,           // current index in `input`
        j,           // current chunk
        saveStack = [],   // holds state for backtracking
        furthest,    // furthest index the parser has gone to
        chunks,      // chunkified input
        current,     // current chunk
        currentPos,  // index of current chunk, in `input`
        parser,
        parsers,
        rootFilename = env && env.filename;

    // Top parser on an import tree must be sure there is one "env"
    // which will then be passed around by reference.
    if (!(env instanceof tree.parseEnv)) {
        env = new tree.parseEnv(env);
    }

    var imports = this.imports = {
        paths: env.paths || [],  // Search paths, when importing
        queue: [],               // Files which haven't been imported yet
        files: env.files,        // Holds the imported parse trees
        contents: env.contents,  // Holds the imported file contents
        contentsIgnoredChars: env.contentsIgnoredChars, // lines inserted, not in the original less
        mime: env.mime,         // MIME type of .less files
        error: null,             // Error in parsing/evaluating an import
        push: function (path, currentFileInfo, importOptions, callback) {
            var parserImports = this;
            this.queue.push(path);

            var fileParsedFunc = function (e, root, fullPath) {
                parserImports.queue.splice(parserImports.queue.indexOf(path), 1); // Remove the path from the queue

                var importedPreviously = fullPath === rootFilename;

                parserImports.files[fullPath] = root;                        // Store the root

                if (e && !parserImports.error) {
                    parserImports.error = e;
                }

                callback(e, root, importedPreviously, fullPath);
            };

            if (less.Parser.importer) {
                less.Parser.importer(path, currentFileInfo, fileParsedFunc, env);
            } else {
                less.Parser.fileLoader(path, currentFileInfo, function (e, contents, fullPath, newFileInfo) {
                    if (e) {
                        fileParsedFunc(e);
                        return;
                    }

                    var newEnv = new tree.parseEnv(env);

                    newEnv.currentFileInfo = newFileInfo;
                    newEnv.processImports = false;
                    newEnv.contents[fullPath] = contents;

                    if (currentFileInfo.reference || importOptions.reference) {
                        newFileInfo.reference = true;
                    }

                    if (importOptions.inline) {
                        fileParsedFunc(null, contents, fullPath);
                    } else {
                        new (less.Parser)(newEnv).parse(contents, function (e, root) {
                            fileParsedFunc(e, root, fullPath);
                        });
                    }
                }, env);
            }
        }
    };

    function save() {
        currentPos = i;
        saveStack.push({current: current, i: i, j: j});
    }

    function restore() {
        var state = saveStack.pop();
        current = state.current;
        currentPos = i = state.i;
        j = state.j;
    }

    function forget() {
        saveStack.pop();
    }

    function sync() {
        if (i > currentPos) {
            current = current.slice(i - currentPos);
            currentPos = i;
        }
    }

    function isWhitespace(str, pos) {
        var code = str.charCodeAt(pos | 0);
        return (code <= 32) && (code === 32 || code === 10 || code === 9);
    }

    //
    // Parse from a token, regexp or string, and move forward if match
    //
    function $(tok) {
        var tokType = typeof tok,
            match, length;

        // Either match a single character in the input,
        // or match a regexp in the current chunk (`current`).
        //
        if (tokType === "string") {
            if (input.charAt(i) !== tok) {
                return null;
            }
            skipWhitespace(1);
            return tok;
        }

        // regexp
        sync();
        if (!(match = tok.exec(current))) {
            return null;
        }

        length = match[0].length;

        // The match is confirmed, add the match length to `i`,
        // and consume any extra white-space characters (' ' || '\n')
        // which come after that. The reason for this is that LeSS's
        // grammar is mostly white-space insensitive.
        //
        skipWhitespace(length);

        if (typeof(match) === 'string') {
            return match;
        } else {
            return match.length === 1 ? match[0] : match;
        }
    }

    // Specialization of $(tok)
    function $re(tok) {
        if (i > currentPos) {
            current = current.slice(i - currentPos);
            currentPos = i;
        }
        var m = tok.exec(current);
        if (!m) {
            return null;
        }

        skipWhitespace(m[0].length);
        if (typeof m === "string") {
            return m;
        }

        return m.length === 1 ? m[0] : m;
    }

    var _$re = $re;

    // Specialization of $(tok)
    function $char(tok) {
        if (input.charAt(i) !== tok) {
            return null;
        }
        skipWhitespace(1);
        return tok;
    }

    function skipWhitespace(length) {
        var oldi = i, oldj = j,
            curr = i - currentPos,
            endIndex = i + current.length - curr,
            mem = (i += length),
            inp = input,
            c;

        for (; i < endIndex; i++) {
            c = inp.charCodeAt(i);
            if (c > 32) {
                break;
            }

            if ((c !== 32) && (c !== 10) && (c !== 9) && (c !== 13)) {
                break;
            }
        }

        current = current.slice(length + i - mem + curr);
        currentPos = i;

        if (!current.length && (j < chunks.length - 1)) {
            current = chunks[++j];
            skipWhitespace(0); // skip space at the beginning of a chunk
            return true; // things changed
        }

        return oldi !== i || oldj !== j;
    }

    function expect(arg, msg, index) {
        // some older browsers return typeof 'function' for RegExp
        var result = (Object.prototype.toString.call(arg) === '[object Function]') ? arg.call(parsers) : $(arg);
        if (result) {
            return result;
        }
        error(msg || (typeof(arg) === 'string' ? "expected '" + arg + "' got '" + input.charAt(i) + "'"
            : "unexpected token"));
    }

    // Specialization of expect()
    function expectChar(arg, msg) {
        if (input.charAt(i) === arg) {
            skipWhitespace(1);
            return arg;
        }
        error(msg || "expected '" + arg + "' got '" + input.charAt(i) + "'");
    }

    function error(msg, type) {
        var e = new Error(msg);
        e.index = i;
        e.type = type || 'Syntax';
        throw e;
    }

    // Same as $(), but don't change the state of the parser,
    // just return the match.
    function peek(tok) {
        if (typeof(tok) === 'string') {
            return input.charAt(i) === tok;
        } else {
            return tok.test(current);
        }
    }

    // Specialization of peek()
    function peekChar(tok) {
        return input.charAt(i) === tok;
    }


    function getInput(e, env) {
        if (e.filename && env.currentFileInfo.filename && (e.filename !== env.currentFileInfo.filename)) {
            return parser.imports.contents[e.filename];
        } else {
            return input;
        }
    }

    function getLocation(index, inputStream) {
        var n = index + 1,
            line = null,
            column = -1;

        while (--n >= 0 && inputStream.charAt(n) !== '\n') {
            column++;
        }

        if (typeof index === 'number') {
            line = (inputStream.slice(0, index).match(/\n/g) || "").length;
        }

        return {
            line: line,
            column: column
        };
    }

    function getDebugInfo(index, inputStream, env) {
        var filename = env.currentFileInfo.filename;
        if (less.mode !== 'browser' && less.mode !== 'rhino') {
            filename = require('path').resolve(filename);
        }

        return {
            lineNumber: getLocation(index, inputStream).line + 1,
            fileName: filename
        };
    }

    function LessError(e, env) {
        var input = getInput(e, env),
            loc = getLocation(e.index, input),
            line = loc.line,
            col = loc.column,
            callLine = e.call && getLocation(e.call, input).line,
            lines = input.split('\n');

        this.type = e.type || 'Syntax';
        this.message = e.message;
        this.filename = e.filename || env.currentFileInfo.filename;
        this.index = e.index;
        this.line = typeof(line) === 'number' ? line + 1 : null;
        this.callLine = callLine + 1;
        this.callExtract = lines[callLine];
        this.stack = e.stack;
        this.column = col;
        this.extract = [
            lines[line - 1],
            lines[line],
            lines[line + 1]
        ];
    }

    LessError.prototype = new Error();
    LessError.prototype.constructor = LessError;

    this.env = env = env || {};

    // The optimization level dictates the thoroughness of the parser,
    // the lower the number, the less nodes it will create in the tree.
    // This could matter for debugging, or if you want to access
    // the individual nodes in the tree.
    this.optimization = ('optimization' in this.env) ? this.env.optimization : 1;

    //
    // The Parser
    //
    parser = {

        imports: imports,
        //
        // Parse an input string into an abstract syntax tree,
        // @param str A string containing 'less' markup
        // @param callback call `callback` when done.
        // @param [additionalData] An optional map which can contains vars - a map (key, value) of variables to apply
        //
        parse: function (str, callback, additionalData) {
            var root, line, lines, error = null, globalVars, modifyVars, preText = "";

            i = j = currentPos = furthest = 0;

            globalVars = (additionalData && additionalData.globalVars) ? less.Parser.serializeVars(additionalData.globalVars) + '\n' : '';
            modifyVars = (additionalData && additionalData.modifyVars) ? '\n' + less.Parser.serializeVars(additionalData.modifyVars) : '';

            if (globalVars || (additionalData && additionalData.banner)) {
                preText = ((additionalData && additionalData.banner) ? additionalData.banner : "") + globalVars;
                parser.imports.contentsIgnoredChars[env.currentFileInfo.filename] = preText.length;
            }

            str = str.replace(/\r\n/g, '\n');
            // Remove potential UTF Byte Order Mark
            input = str = preText + str.replace(/^\uFEFF/, '') + modifyVars;
            parser.imports.contents[env.currentFileInfo.filename] = str;

            // Split the input into chunks.
            chunks = (function (input) {
                var len = input.length, level = 0, parenLevel = 0,
                    lastOpening, lastOpeningParen, lastMultiComment, lastMultiCommentEndBrace,
                    chunks = [], emitFrom = 0,
                    parserCurrentIndex, currentChunkStartIndex, cc, cc2, matched;

                function fail(msg, index) {
                    error = new (LessError)({
                        index: index || parserCurrentIndex,
                        type: 'Parse',
                        message: msg,
                        filename: env.currentFileInfo.filename
                    }, env);
                }

                function emitChunk(force) {
                    var len = parserCurrentIndex - emitFrom;
                    if (((len < 512) && !force) || !len) {
                        return;
                    }
                    chunks.push(input.slice(emitFrom, parserCurrentIndex + 1));
                    emitFrom = parserCurrentIndex + 1;
                }

                for (parserCurrentIndex = 0; parserCurrentIndex < len; parserCurrentIndex++) {
                    cc = input.charCodeAt(parserCurrentIndex);
                    if (((cc >= 97) && (cc <= 122)) || (cc < 34)) {
                        // a-z or whitespace
                        continue;
                    }

                    switch (cc) {
                        case 40:                        // (
                            parenLevel++;
                            lastOpeningParen = parserCurrentIndex;
                            continue;
                        case 41:                        // )
                            if (--parenLevel < 0) {
                                return fail("missing opening `(`");
                            }
                            continue;
                        case 59:                        // ;
                            if (!parenLevel) {
                                emitChunk();
                            }
                            continue;
                        case 123:                       // {
                            level++;
                            lastOpening = parserCurrentIndex;
                            continue;
                        case 125:                       // }
                            if (--level < 0) {
                                return fail("missing opening `{`");
                            }
                            if (!level && !parenLevel) {
                                emitChunk();
                            }
                            continue;
                        case 92:                        // \
                            if (parserCurrentIndex < len - 1) {
                                parserCurrentIndex++;
                                continue;
                            }
                            return fail("unescaped `\\`");
                        case 34:
                        case 39:
                        case 96:                        // ", ' and `
                            matched = 0;
                            currentChunkStartIndex = parserCurrentIndex;
                            for (parserCurrentIndex = parserCurrentIndex + 1; parserCurrentIndex < len; parserCurrentIndex++) {
                                cc2 = input.charCodeAt(parserCurrentIndex);
                                if (cc2 > 96) {
                                    continue;
                                }
                                if (cc2 == cc) {
                                    matched = 1;
                                    break;
                                }
                                if (cc2 == 92) {        // \
                                    if (parserCurrentIndex == len - 1) {
                                        return fail("unescaped `\\`");
                                    }
                                    parserCurrentIndex++;
                                }
                            }
                            if (matched) {
                                continue;
                            }
                            return fail("unmatched `" + String.fromCharCode(cc) + "`", currentChunkStartIndex);
                        case 47:                        // /, check for comment
                            if (parenLevel || (parserCurrentIndex == len - 1)) {
                                continue;
                            }
                            cc2 = input.charCodeAt(parserCurrentIndex + 1);
                            if (cc2 == 47) {
                                // //, find lnfeed
                                for (parserCurrentIndex = parserCurrentIndex + 2; parserCurrentIndex < len; parserCurrentIndex++) {
                                    cc2 = input.charCodeAt(parserCurrentIndex);
                                    if ((cc2 <= 13) && ((cc2 == 10) || (cc2 == 13))) {
                                        break;
                                    }
                                }
                            } else if (cc2 == 42) {
                                // /*, find */
                                lastMultiComment = currentChunkStartIndex = parserCurrentIndex;
                                for (parserCurrentIndex = parserCurrentIndex + 2; parserCurrentIndex < len - 1; parserCurrentIndex++) {
                                    cc2 = input.charCodeAt(parserCurrentIndex);
                                    if (cc2 == 125) {
                                        lastMultiCommentEndBrace = parserCurrentIndex;
                                    }
                                    if (cc2 != 42) {
                                        continue;
                                    }
                                    if (input.charCodeAt(parserCurrentIndex + 1) == 47) {
                                        break;
                                    }
                                }
                                if (parserCurrentIndex == len - 1) {
                                    return fail("missing closing `*/`", currentChunkStartIndex);
                                }
                                parserCurrentIndex++;
                            }
                            continue;
                        case 42:                       // *, check for unmatched */
                            if ((parserCurrentIndex < len - 1) && (input.charCodeAt(parserCurrentIndex + 1) == 47)) {
                                return fail("unmatched `/*`");
                            }
                            continue;
                    }
                }

                if (level !== 0) {
                    if ((lastMultiComment > lastOpening) && (lastMultiCommentEndBrace > lastMultiComment)) {
                        return fail("missing closing `}` or `*/`", lastOpening);
                    } else {
                        return fail("missing closing `}`", lastOpening);
                    }
                } else if (parenLevel !== 0) {
                    return fail("missing closing `)`", lastOpeningParen);
                }

                emitChunk(true);
                return chunks;
            })(str);

            if (error) {
                return callback(new (LessError)(error, env));
            }

            current = chunks[0];

            // Start with the primary rule.
            // The whole syntax tree is held under a Ruleset node,
            // with the `root` property set to true, so no `{}` are
            // output. The callback is called when the input is parsed.
            try {
                root = new (tree.Ruleset)(null, this.parsers.primary());
                root.root = true;
                root.firstRoot = true;
            } catch (e) {
                return callback(new (LessError)(e, env));
            }

            root.toCSS = (function (evaluate) {
                return function (options, variables) {
                    options = options || {};
                    var evaldRoot,
                        css,
                        evalEnv = new tree.evalEnv(options);

                    //
                    // Allows setting variables with a hash, so:
                    //
                    //   `{ color: new(tree.Color)('#f01') }` will become:
                    //
                    //   new(tree.Rule)('@color',
                    //     new(tree.Value)([
                    //       new(tree.Expression)([
                    //         new(tree.Color)('#f01')
                    //       ])
                    //     ])
                    //   )
                    //
                    if (typeof(variables) === 'object' && !Array.isArray(variables)) {
                        variables = Object.keys(variables).map(function (k) {
                            var value = variables[k];

                            if (!(value instanceof tree.Value)) {
                                if (!(value instanceof tree.Expression)) {
                                    value = new (tree.Expression)([value]);
                                }
                                value = new (tree.Value)([value]);
                            }
                            return new (tree.Rule)('@' + k, value, false, null, 0);
                        });
                        evalEnv.frames = [new (tree.Ruleset)(null, variables)];
                    }

                    try {
                        var preEvalVisitors = [],
                            visitors = [
                                new (tree.joinSelectorVisitor)(),
                                new (tree.processExtendsVisitor)(),
                                new (tree.toCSSVisitor)({compress: Boolean(options.compress)})
                            ], i, root = this;

                        if (options.plugins) {
                            for (i = 0; i < options.plugins.length; i++) {
                                if (options.plugins[i].isPreEvalVisitor) {
                                    preEvalVisitors.push(options.plugins[i]);
                                } else {
                                    if (options.plugins[i].isPreVisitor) {
                                        visitors.splice(0, 0, options.plugins[i]);
                                    } else {
                                        visitors.push(options.plugins[i]);
                                    }
                                }
                            }
                        }

                        for (i = 0; i < preEvalVisitors.length; i++) {
                            preEvalVisitors[i].run(root);
                        }

                        evaldRoot = evaluate.call(root, evalEnv);

                        for (i = 0; i < visitors.length; i++) {
                            visitors[i].run(evaldRoot);
                        }

                        if (options.sourceMap) {
                            evaldRoot = new tree.sourceMapOutput(
                                {
                                    contentsIgnoredCharsMap: parser.imports.contentsIgnoredChars,
                                    writeSourceMap: options.writeSourceMap,
                                    rootNode: evaldRoot,
                                    contentsMap: parser.imports.contents,
                                    sourceMapFilename: options.sourceMapFilename,
                                    sourceMapURL: options.sourceMapURL,
                                    outputFilename: options.sourceMapOutputFilename,
                                    sourceMapBasepath: options.sourceMapBasepath,
                                    sourceMapRootpath: options.sourceMapRootpath,
                                    outputSourceFiles: options.outputSourceFiles,
                                    sourceMapGenerator: options.sourceMapGenerator
                                });
                        }

                        css = evaldRoot.toCSS({
                            compress: Boolean(options.compress),
                            dumpLineNumbers: env.dumpLineNumbers,
                            strictUnits: Boolean(options.strictUnits),
                            numPrecision: 8
                        });
                    } catch (e) {
                        throw new (LessError)(e, env);
                    }

                    if (options.cleancss && less.mode === 'node') {
                        var CleanCSS = require('clean-css'),
                            cleancssOptions = options.cleancssOptions || {};

                        if (cleancssOptions.keepSpecialComments === undefined) {
                            cleancssOptions.keepSpecialComments = "*";
                        }
                        cleancssOptions.processImport = false;
                        cleancssOptions.noRebase = true;
                        if (cleancssOptions.noAdvanced === undefined) {
                            cleancssOptions.noAdvanced = true;
                        }

                        return new CleanCSS(cleancssOptions).minify(css);
                    } else if (options.compress) {
                        return css.replace(/(^(\s)+)|((\s)+$)/g, "");
                    } else {
                        return css;
                    }
                };
            })(root.eval);

            // If `i` is smaller than the `input.length - 1`,
            // it means the parser wasn't able to parse the whole
            // string, so we've got a parsing error.
            //
            // We try to extract a \n delimited string,
            // showing the line where the parse error occured.
            // We split it up into two parts (the part which parsed,
            // and the part which didn't), so we can color them differently.
            if (i < input.length - 1) {
                i = furthest;
                var loc = getLocation(i, input);
                lines = input.split('\n');
                line = loc.line + 1;

                error = {
                    type: "Parse",
                    message: "Unrecognised input",
                    index: i,
                    filename: env.currentFileInfo.filename,
                    line: line,
                    column: loc.column,
                    extract: [
                        lines[line - 2],
                        lines[line - 1],
                        lines[line]
                    ]
                };
            }

            var finish = function (e) {
                e = error || e || parser.imports.error;

                if (e) {
                    if (!(e instanceof LessError)) {
                        e = new (LessError)(e, env);
                    }

                    return callback(e);
                }
                else {
                    return callback(null, root);
                }
            };

            if (env.processImports !== false) {
                new tree.importVisitor(this.imports, finish)
                    .run(root);
            } else {
                return finish();
            }
        },

        //
        // Here in, the parsing rules/functions
        //
        // The basic structure of the syntax tree generated is as follows:
        //
        //   Ruleset ->  Rule -> Value -> Expression -> Entity
        //
        // Here's some Less code:
        //
        //    .class {
        //      color: #fff;
        //      border: 1px solid #000;
        //      width: @w + 4px;
        //      > .child {...}
        //    }
        //
        // And here's what the parse tree might look like:
        //
        //     Ruleset (Selector '.class', [
        //         Rule ("color",  Value ([Expression [Color #fff]]))
        //         Rule ("border", Value ([Expression [Dimension 1px][Keyword "solid"][Color #000]]))
        //         Rule ("width",  Value ([Expression [Operation "+" [Variable "@w"][Dimension 4px]]]))
        //         Ruleset (Selector [Element '>', '.child'], [...])
        //     ])
        //
        //  In general, most rules will try to parse a token with the `$()` function, and if the return
        //  value is truly, will return a new node, of the relevant type. Sometimes, we need to check
        //  first, before parsing, that's when we use `peek()`.
        //
        parsers: parsers = {
            //
            // The `primary` rule is the *entry* and *exit* point of the parser.
            // The rules here can appear at any level of the parse tree.
            //
            // The recursive nature of the grammar is an interplay between the `block`
            // rule, which represents `{ ... }`, the `ruleset` rule, and this `primary` rule,
            // as represented by this simplified grammar:
            //
            //     primary  →  (ruleset | rule)+
            //     ruleset  →  selector+ block
            //     block    →  '{' primary '}'
            //
            // Only at one point is the primary rule not called from the
            // block rule: at the root level.
            //
            primary: function () {
                var mixin = this.mixin, $re = _$re, root = [], node;

                while (current) {
                    node = this.extendRule() || mixin.definition() || this.rule() || this.ruleset() ||
                    mixin.call() || this.comment() || this.rulesetCall() || this.directive();
                    if (node) {
                        root.push(node);
                    } else {
                        if (!($re(/^[\s\n]+/) || $re(/^;+/))) {
                            break;
                        }
                    }
                    if (peekChar('}')) {
                        break;
                    }
                }

                return root;
            },

            // We create a Comment node for CSS comments `/* */`,
            // but keep the LeSS comments `//` silent, by just skipping
            // over them.
            comment: function () {
                var comment;

                if (input.charAt(i) !== '/') {
                    return;
                }

                if (input.charAt(i + 1) === '/') {
                    return new (tree.Comment)($re(/^\/\/.*/), true, i, env.currentFileInfo);
                }
                comment = $re(/^\/\*(?:[^*]|\*+[^\/*])*\*+\/\n?/);
                if (comment) {
                    return new (tree.Comment)(comment, false, i, env.currentFileInfo);
                }
            },

            comments: function () {
                var comment, comments = [];

                while (true) {
                    comment = this.comment();
                    if (!comment) {
                        break;
                    }
                    comments.push(comment);
                }

                return comments;
            },

            //
            // Entities are tokens which can be found inside an Expression
            //
            entities: {
                //
                // A string, which supports escaping " and '
                //
                //     "milky way" 'he\'s the one!'
                //
                quoted: function () {
                    var str, j = i, e, index = i;

                    if (input.charAt(j) === '~') {
                        j++;
                        e = true;
                    } // Escaped strings
                    if (input.charAt(j) !== '"' && input.charAt(j) !== "'") {
                        return;
                    }

                    if (e) {
                        $char('~');
                    }

                    str = $re(/^"((?:[^"\\\r\n]|\\.)*)"|'((?:[^'\\\r\n]|\\.)*)'/);
                    if (str) {
                        return new (tree.Quoted)(str[0], str[1] || str[2], e, index, env.currentFileInfo);
                    }
                },

                //
                // A catch-all word, such as:
                //
                //     black border-collapse
                //
                keyword: function () {
                    var k;

                    k = $re(/^%|^[_A-Za-z-][_A-Za-z0-9-]*/);
                    if (k) {
                        var color = tree.Color.fromKeyword(k);
                        if (color) {
                            return color;
                        }
                        return new (tree.Keyword)(k);
                    }
                },

                //
                // A function call
                //
                //     rgb(255, 0, 255)
                //
                // We also try to catch IE's `alpha()`, but let the `alpha` parser
                // deal with the details.
                //
                // The arguments are parsed with the `entities.arguments` parser.
                //
                call: function () {
                    var name, nameLC, args, alpha_ret, index = i;

                    name = /^([\w-]+|%|progid:[\w\.]+)\(/.exec(current);
                    if (!name) {
                        return;
                    }

                    name = name[1];
                    nameLC = name.toLowerCase();
                    if (nameLC === 'url') {
                        return null;
                    }

                    i += name.length;

                    if (nameLC === 'alpha') {
                        alpha_ret = parsers.alpha();
                        if (typeof alpha_ret !== 'undefined') {
                            return alpha_ret;
                        }
                    }

                    $char('('); // Parse the '(' and consume whitespace.

                    args = this.arguments();

                    if (!$char(')')) {
                        return;
                    }

                    if (name) {
                        return new (tree.Call)(name, args, index, env.currentFileInfo);
                    }
                },
                arguments: function () {
                    var args = [], arg;

                    while (true) {
                        arg = this.assignment() || parsers.expression();
                        if (!arg) {
                            break;
                        }
                        args.push(arg);
                        if (!$char(',')) {
                            break;
                        }
                    }
                    return args;
                },
                literal: function () {
                    return this.dimension() ||
                        this.color() ||
                        this.quoted() ||
                        this.unicodeDescriptor();
                },

                // Assignments are argument entities for calls.
                // They are present in ie filter properties as shown below.
                //
                //     filter: progid:DXImageTransform.Microsoft.Alpha( *opacity=50* )
                //

                assignment: function () {
                    var key, value;
                    key = $re(/^\w+(?=\s?=)/i);
                    if (!key) {
                        return;
                    }
                    if (!$char('=')) {
                        return;
                    }
                    value = parsers.entity();
                    if (value) {
                        return new (tree.Assignment)(key, value);
                    }
                },

                //
                // Parse url() tokens
                //
                // We use a specific rule for urls, because they don't really behave like
                // standard function calls. The difference is that the argument doesn't have
                // to be enclosed within a string, so it can't be parsed as an Expression.
                //
                url: function () {
                    var value;

                    if (input.charAt(i) !== 'u' || !$re(/^url\(/)) {
                        return;
                    }

                    value = this.quoted() || this.variable() ||
                    $re(/^(?:(?:\\[\(\)'"])|[^\(\)'"])+/) || "";

                    expectChar(')');

                    return new (tree.URL)((value.value != null || value instanceof tree.Variable)
                        ? value : new (tree.Anonymous)(value), env.currentFileInfo);
                },

                //
                // A Variable entity, such as `@fink`, in
                //
                //     width: @fink + 2px
                //
                // We use a different parser for variable definitions,
                // see `parsers.variable`.
                //
                variable: function () {
                    var name, index = i;

                    if (input.charAt(i) === '@' && (name = $re(/^@@?[\w-]+/))) {
                        return new (tree.Variable)(name, index, env.currentFileInfo);
                    }
                },

                // A variable entity useing the protective {} e.g. @{var}
                variableCurly: function () {
                    var curly, index = i;

                    if (input.charAt(i) === '@' && (curly = $re(/^@\{([\w-]+)\}/))) {
                        return new (tree.Variable)("@" + curly[1], index, env.currentFileInfo);
                    }
                },

                //
                // A Hexadecimal color
                //
                //     #4F3C2F
                //
                // `rgb` and `hsl` colors are parsed through the `entities.call` parser.
                //
                color: function () {
                    var rgb;

                    if (input.charAt(i) === '#' && (rgb = $re(/^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})/))) {
                        var colorCandidateString = rgb.input.match(/^#([\w]+).*/); // strip colons, brackets, whitespaces and other characters that should not definitely be part of color string
                        colorCandidateString = colorCandidateString[1];
                        if (!colorCandidateString.match(/^[A-Fa-f0-9]+$/)) { // verify if candidate consists only of allowed HEX characters
                            error("Invalid HEX color code");
                        }
                        return new (tree.Color)(rgb[1]);
                    }
                },

                //
                // A Dimension, that is, a number and a unit
                //
                //     0.5em 95%
                //
                dimension: function () {
                    var value, c = input.charCodeAt(i);
                    //Is the first char of the dimension 0-9, '.', '+' or '-'
                    if ((c > 57 || c < 43) || c === 47 || c == 44) {
                        return;
                    }

                    value = $re(/^([+-]?\d*\.?\d+)(%|[a-z]+)?/);
                    if (value) {
                        return new (tree.Dimension)(value[1], value[2]);
                    }
                },

                //
                // A unicode descriptor, as is used in unicode-range
                //
                // U+0??  or U+00A1-00A9
                //
                unicodeDescriptor: function () {
                    var ud;

                    ud = $re(/^U\+[0-9a-fA-F?]+(\-[0-9a-fA-F?]+)?/);
                    if (ud) {
                        return new (tree.UnicodeDescriptor)(ud[0]);
                    }
                },

                //
                // JavaScript code to be evaluated
                //
                //     `window.location.href`
                //
                javascript: function () {
                    var str, j = i, e;

                    if (input.charAt(j) === '~') {
                        j++;
                        e = true;
                    } // Escaped strings
                    if (input.charAt(j) !== '`') {
                        return;
                    }
                    if (env.javascriptEnabled !== undefined && !env.javascriptEnabled) {
                        error("You are using JavaScript, which has been disabled.");
                    }

                    if (e) {
                        $char('~');
                    }

                    str = $re(/^`([^`]*)`/);
                    if (str) {
                        return new (tree.JavaScript)(str[1], i, e);
                    }
                }
            },

            //
            // The variable part of a variable definition. Used in the `rule` parser
            //
            //     @fink:
            //
            variable: function () {
                var name;

                if (input.charAt(i) === '@' && (name = $re(/^(@[\w-]+)\s*:/))) {
                    return name[1];
                }
            },

            //
            // The variable part of a variable definition. Used in the `rule` parser
            //
            //     @fink();
            //
            rulesetCall: function () {
                var name;

                if (input.charAt(i) === '@' && (name = $re(/^(@[\w-]+)\s*\(\s*\)\s*;/))) {
                    return new tree.RulesetCall(name[1]);
                }
            },

            //
            // extend syntax - used to extend selectors
            //
            extend: function (isRule) {
                var elements, e, index = i, option, extendList, extend;

                if (!(isRule ? $re(/^&:extend\(/) : $re(/^:extend\(/))) {
                    return;
                }

                do {
                    option = null;
                    elements = null;
                    while (!(option = $re(/^(all)(?=\s*(\)|,))/))) {
                        e = this.element();
                        if (!e) {
                            break;
                        }
                        if (elements) {
                            elements.push(e);
                        } else {
                            elements = [e];
                        }
                    }

                    option = option && option[1];
                    if (!elements)
                        error("Missing target selector for :extend().");
                    extend = new (tree.Extend)(new (tree.Selector)(elements), option, index);
                    if (extendList) {
                        extendList.push(extend);
                    } else {
                        extendList = [extend];
                    }

                } while ($char(","));

                expect(/^\)/);

                if (isRule) {
                    expect(/^;/);
                }

                return extendList;
            },

            //
            // extendRule - used in a rule to extend all the parent selectors
            //
            extendRule: function () {
                return this.extend(true);
            },

            //
            // Mixins
            //
            mixin: {
                //
                // A Mixin call, with an optional argument list
                //
                //     #mixins > .square(#fff);
                //     .rounded(4px, black);
                //     .button;
                //
                // The `while` loop is there because mixins can be
                // namespaced, but we only support the child and descendant
                // selector for now.
                //
                call: function () {
                    var s = input.charAt(i), important = false, index = i, elemIndex,
                        elements, elem, e, c, args;

                    if (s !== '.' && s !== '#') {
                        return;
                    }

                    save(); // stop us absorbing part of an invalid selector

                    while (true) {
                        elemIndex = i;
                        e = $re(/^[#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/);
                        if (!e) {
                            break;
                        }
                        elem = new (tree.Element)(c, e, elemIndex, env.currentFileInfo);
                        if (elements) {
                            elements.push(elem);
                        } else {
                            elements = [elem];
                        }
                        c = $char('>');
                    }

                    if (elements) {
                        if ($char('(')) {
                            args = this.args(true).args;
                            expectChar(')');
                        }

                        if (parsers.important()) {
                            important = true;
                        }

                        if (parsers.end()) {
                            forget();
                            return new (tree.mixin.Call)(elements, args, index, env.currentFileInfo, important);
                        }
                    }

                    restore();
                },
                args: function (isCall) {
                    var parsers = parser.parsers, entities = parsers.entities,
                        returner = {args: null, variadic: false},
                        expressions = [], argsSemiColon = [], argsComma = [],
                        isSemiColonSeperated, expressionContainsNamed, name, nameLoop, value, arg;

                    save();

                    while (true) {
                        if (isCall) {
                            arg = parsers.detachedRuleset() || parsers.expression();
                        } else {
                            parsers.comments();
                            if (input.charAt(i) === '.' && $re(/^\.{3}/)) {
                                returner.variadic = true;
                                if ($char(";") && !isSemiColonSeperated) {
                                    isSemiColonSeperated = true;
                                }
                                (isSemiColonSeperated ? argsSemiColon : argsComma)
                                    .push({variadic: true});
                                break;
                            }
                            arg = entities.variable() || entities.literal() || entities.keyword();
                        }

                        if (!arg) {
                            break;
                        }

                        nameLoop = null;
                        if (arg.throwAwayComments) {
                            arg.throwAwayComments();
                        }
                        value = arg;
                        var val = null;

                        if (isCall) {
                            // Variable
                            if (arg.value && arg.value.length == 1) {
                                val = arg.value[0];
                            }
                        } else {
                            val = arg;
                        }

                        if (val && val instanceof tree.Variable) {
                            if ($char(':')) {
                                if (expressions.length > 0) {
                                    if (isSemiColonSeperated) {
                                        error("Cannot mix ; and , as delimiter types");
                                    }
                                    expressionContainsNamed = true;
                                }

                                // we do not support setting a ruleset as a default variable - it doesn't make sense
                                // However if we do want to add it, there is nothing blocking it, just don't error
                                // and remove isCall dependency below
                                value = (isCall && parsers.detachedRuleset()) || parsers.expression();

                                if (!value) {
                                    if (isCall) {
                                        error("could not understand value for named argument");
                                    } else {
                                        restore();
                                        returner.args = [];
                                        return returner;
                                    }
                                }
                                nameLoop = (name = val.name);
                            } else if (!isCall && $re(/^\.{3}/)) {
                                returner.variadic = true;
                                if ($char(";") && !isSemiColonSeperated) {
                                    isSemiColonSeperated = true;
                                }
                                (isSemiColonSeperated ? argsSemiColon : argsComma)
                                    .push({name: arg.name, variadic: true});
                                break;
                            } else if (!isCall) {
                                name = nameLoop = val.name;
                                value = null;
                            }
                        }

                        if (value) {
                            expressions.push(value);
                        }

                        argsComma.push({name: nameLoop, value: value});

                        if ($char(',')) {
                            continue;
                        }

                        if ($char(';') || isSemiColonSeperated) {

                            if (expressionContainsNamed) {
                                error("Cannot mix ; and , as delimiter types");
                            }

                            isSemiColonSeperated = true;

                            if (expressions.length > 1) {
                                value = new (tree.Value)(expressions);
                            }
                            argsSemiColon.push({name: name, value: value});

                            name = null;
                            expressions = [];
                            expressionContainsNamed = false;
                        }
                    }

                    forget();
                    returner.args = isSemiColonSeperated ? argsSemiColon : argsComma;
                    return returner;
                },
                //
                // A Mixin definition, with a list of parameters
                //
                //     .rounded (@radius: 2px, @color) {
                //        ...
                //     }
                //
                // Until we have a finer grained state-machine, we have to
                // do a look-ahead, to make sure we don't have a mixin call.
                // See the `rule` function for more information.
                //
                // We start by matching `.rounded (`, and then proceed on to
                // the argument list, which has optional default values.
                // We store the parameters in `params`, with a `value` key,
                // if there is a value, such as in the case of `@radius`.
                //
                // Once we've got our params list, and a closing `)`, we parse
                // the `{...}` block.
                //
                definition: function () {
                    var name, params = [], match, ruleset, cond, variadic = false;
                    if ((input.charAt(i) !== '.' && input.charAt(i) !== '#') ||
                        peek(/^[^{]*\}/)) {
                        return;
                    }

                    save();

                    match = $re(/^([#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+)\s*\(/);
                    if (match) {
                        name = match[1];

                        var argInfo = this.args(false);
                        params = argInfo.args;
                        variadic = argInfo.variadic;

                        // .mixincall("@{a}");
                        // looks a bit like a mixin definition..
                        // also
                        // .mixincall(@a: {rule: set;});
                        // so we have to be nice and restore
                        if (!$char(')')) {
                            furthest = i;
                            restore();
                            return;
                        }

                        parsers.comments();

                        if ($re(/^when/)) { // Guard
                            cond = expect(parsers.conditions, 'expected condition');
                        }

                        ruleset = parsers.block();

                        if (ruleset) {
                            forget();
                            return new (tree.mixin.Definition)(name, params, ruleset, cond, variadic);
                        } else {
                            restore();
                        }
                    } else {
                        forget();
                    }
                }
            },

            //
            // Entities are the smallest recognized token,
            // and can be found inside a rule's value.
            //
            entity: function () {
                var entities = this.entities;

                return entities.literal() || entities.variable() || entities.url() ||
                    entities.call() || entities.keyword() || entities.javascript() ||
                    this.comment();
            },

            //
            // A Rule terminator. Note that we use `peek()` to check for '}',
            // because the `block` rule will be expecting it, but we still need to make sure
            // it's there, if ';' was ommitted.
            //
            end: function () {
                return $char(';') || peekChar('}');
            },

            //
            // IE's alpha function
            //
            //     alpha(opacity=88)
            //
            alpha: function () {
                var value;

                if (!$re(/^\(opacity=/i)) {
                    return;
                }
                value = $re(/^\d+/) || this.entities.variable();
                if (value) {
                    expectChar(')');
                    return new (tree.Alpha)(value);
                }
            },

            //
            // A Selector Element
            //
            //     div
            //     + h1
            //     #socks
            //     input[type="text"]
            //
            // Elements are the building blocks for Selectors,
            // they are made out of a `Combinator` (see combinator rule),
            // and an element name, such as a tag a class, or `*`.
            //
            element: function () {
                var e, c, v, index = i;

                c = this.combinator();

                e = $re(/^(?:\d+\.\d+|\d+)%/) || $re(/^(?:[.#]?|:*)(?:[\w-]|[^\x00-\x9f]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/) ||
                $char('*') || $char('&') || this.attribute() || $re(/^\([^()@]+\)/) || $re(/^[\.#](?=@)/) ||
                this.entities.variableCurly();

                if (!e) {
                    save();
                    if ($char('(')) {
                        if ((v = this.selector()) && $char(')')) {
                            e = new (tree.Paren)(v);
                            forget();
                        } else {
                            restore();
                        }
                    } else {
                        forget();
                    }
                }

                if (e) {
                    return new (tree.Element)(c, e, index, env.currentFileInfo);
                }
            },

            //
            // Combinators combine elements together, in a Selector.
            //
            // Because our parser isn't white-space sensitive, special care
            // has to be taken, when parsing the descendant combinator, ` `,
            // as it's an empty space. We have to check the previous character
            // in the input, to see if it's a ` ` character. More info on how
            // we deal with this in *combinator.js*.
            //
            combinator: function () {
                var c = input.charAt(i);

                if (c === '/') {
                    save();
                    var slashedCombinator = $re(/^\/[a-z]+\//i);
                    if (slashedCombinator) {
                        forget();
                        return new (tree.Combinator)(slashedCombinator);
                    }
                    restore();
                }

                if (c === '>' || c === '+' || c === '~' || c === '|' || c === '^') {
                    i++;
                    if (c === '^' && input.charAt(i) === '^') {
                        c = '^^';
                        i++;
                    }
                    while (isWhitespace(input, i)) {
                        i++;
                    }
                    return new (tree.Combinator)(c);
                } else if (isWhitespace(input, i - 1)) {
                    return new (tree.Combinator)(" ");
                } else {
                    return new (tree.Combinator)(null);
                }
            },
            //
            // A CSS selector (see selector below)
            // with less extensions e.g. the ability to extend and guard
            //
            lessSelector: function () {
                return this.selector(true);
            },
            //
            // A CSS Selector
            //
            //     .class > div + h1
            //     li a:hover
            //
            // Selectors are made out of one or more Elements, see above.
            //
            selector: function (isLess) {
                var index = i, $re = _$re, elements, extendList, c, e, extend, when, condition;

                while ((isLess && (extend = this.extend())) || (isLess && (when = $re(/^when/))) || (e = this.element())) {
                    if (when) {
                        condition = expect(this.conditions, 'expected condition');
                    } else if (condition) {
                        error("CSS guard can only be used at the end of selector");
                    } else if (extend) {
                        if (extendList) {
                            extendList.push(extend);
                        } else {
                            extendList = [extend];
                        }
                    } else {
                        if (extendList) {
                            error("Extend can only be used at the end of selector");
                        }
                        c = input.charAt(i);
                        if (elements) {
                            elements.push(e);
                        } else {
                            elements = [e];
                        }
                        e = null;
                    }
                    if (c === '{' || c === '}' || c === ';' || c === ',' || c === ')') {
                        break;
                    }
                }

                if (elements) {
                    return new (tree.Selector)(elements, extendList, condition, index, env.currentFileInfo);
                }
                if (extendList) {
                    error("Extend must be used to extend a selector, it cannot be used on its own");
                }
            },
            attribute: function () {
                if (!$char('[')) {
                    return;
                }

                var entities = this.entities,
                    key, val, op;

                if (!(key = entities.variableCurly())) {
                    key = expect(/^(?:[_A-Za-z0-9-\*]*\|)?(?:[_A-Za-z0-9-]|\\.)+/);
                }

                op = $re(/^[|~*$^]?=/);
                if (op) {
                    val = entities.quoted() || $re(/^[0-9]+%/) || $re(/^[\w-]+/) || entities.variableCurly();
                }

                expectChar(']');

                return new (tree.Attribute)(key, op, val);
            },

            //
            // The `block` rule is used by `ruleset` and `mixin.definition`.
            // It's a wrapper around the `primary` rule, with added `{}`.
            //
            block: function () {
                var content;
                if ($char('{') && (content = this.primary()) && $char('}')) {
                    return content;
                }
            },

            blockRuleset: function () {
                var block = this.block();

                if (block) {
                    block = new tree.Ruleset(null, block);
                }
                return block;
            },

            detachedRuleset: function () {
                var blockRuleset = this.blockRuleset();
                if (blockRuleset) {
                    return new tree.DetachedRuleset(blockRuleset);
                }
            },

            //
            // div, .class, body > p {...}
            //
            ruleset: function () {
                var selectors, s, rules, debugInfo;

                save();

                if (env.dumpLineNumbers) {
                    debugInfo = getDebugInfo(i, input, env);
                }

                while (true) {
                    s = this.lessSelector();
                    if (!s) {
                        break;
                    }
                    if (selectors) {
                        selectors.push(s);
                    } else {
                        selectors = [s];
                    }
                    this.comments();
                    if (s.condition && selectors.length > 1) {
                        error("Guards are only currently allowed on a single selector.");
                    }
                    if (!$char(',')) {
                        break;
                    }
                    if (s.condition) {
                        error("Guards are only currently allowed on a single selector.");
                    }
                    this.comments();
                }

                if (selectors && (rules = this.block())) {
                    forget();
                    var ruleset = new (tree.Ruleset)(selectors, rules, env.strictImports);
                    if (env.dumpLineNumbers) {
                        ruleset.debugInfo = debugInfo;
                    }
                    return ruleset;
                } else {
                    // Backtrack
                    furthest = i;
                    restore();
                }
            },
            rule: function (tryAnonymous) {
                var name, value, startOfRule = i, c = input.charAt(startOfRule), important, merge, isVariable;

                if (c === '.' || c === '#' || c === '&') {
                    return;
                }

                save();

                name = this.variable() || this.ruleProperty();
                if (name) {
                    isVariable = typeof name === "string";

                    if (isVariable) {
                        value = this.detachedRuleset();
                    }

                    this.comments();
                    if (!value) {
                        // prefer to try to parse first if its a variable or we are compressing
                        // but always fallback on the other one
                        value = !tryAnonymous && (env.compress || isVariable) ?
                            (this.value() || this.anonymousValue()) :
                            (this.anonymousValue() || this.value());

                        important = this.important();

                        // a name returned by this.ruleProperty() is always an array of the form:
                        // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
                        // where each item is a tree.Keyword or tree.Variable
                        merge = !isVariable && name.pop().value;
                    }

                    if (value && this.end()) {
                        forget();
                        return new (tree.Rule)(name, value, important, merge, startOfRule, env.currentFileInfo);
                    } else {
                        furthest = i;
                        restore();
                        if (value && !tryAnonymous) {
                            return this.rule(true);
                        }
                    }
                } else {
                    forget();
                }
            },
            anonymousValue: function () {
                var match;
                match = /^([^@+\/'"*`(;{}-]*);/.exec(current);
                if (match) {
                    i += match[0].length - 1;
                    return new (tree.Anonymous)(match[1]);
                }
            },

            //
            // An @import directive
            //
            //     @import "lib";
            //
            // Depending on our environment, importing is done differently:
            // In the browser, it's an XHR request, in Node, it would be a
            // file-system operation. The function used for importing is
            // stored in `import`, which we pass to the Import constructor.
            //
            "import": function () {
                var path, features, index = i;

                var dir = $re(/^@import?\s+/);

                if (dir) {
                    var options = (dir ? this.importOptions() : null) || {};

                    if ((path = this.entities.quoted() || this.entities.url())) {
                        features = this.mediaFeatures();

                        if (!$(';')) {
                            i = index;
                            error("missing semi-colon or unrecognised media features on import");
                        }
                        features = features && new (tree.Value)(features);
                        return new (tree.Import)(path, features, options, index, env.currentFileInfo);
                    }
                    else {
                        i = index;
                        error("malformed import statement");
                    }
                }
            },

            importOptions: function () {
                var o, options = {}, optionName, value;

                // list of options, surrounded by parens
                if (!$char('(')) {
                    return null;
                }
                do {
                    o = this.importOption();
                    if (o) {
                        optionName = o;
                        value = true;
                        switch (optionName) {
                            case "css":
                                optionName = "less";
                                value = false;
                                break;
                            case "once":
                                optionName = "multiple";
                                value = false;
                                break;
                        }
                        options[optionName] = value;
                        if (!$char(',')) {
                            break;
                        }
                    }
                } while (o);
                expectChar(')');
                return options;
            },

            importOption: function () {
                var opt = $re(/^(less|css|multiple|once|inline|reference)/);
                if (opt) {
                    return opt[1];
                }
            },

            mediaFeature: function () {
                var entities = this.entities, nodes = [], e, p;
                do {
                    e = entities.keyword() || entities.variable();
                    if (e) {
                        nodes.push(e);
                    } else if ($char('(')) {
                        p = this.property();
                        e = this.value();
                        if ($char(')')) {
                            if (p && e) {
                                nodes.push(new (tree.Paren)(new (tree.Rule)(p, e, null, null, i, env.currentFileInfo, true)));
                            } else if (e) {
                                nodes.push(new (tree.Paren)(e));
                            } else {
                                return null;
                            }
                        } else {
                            return null;
                        }
                    }
                } while (e);

                if (nodes.length > 0) {
                    return new (tree.Expression)(nodes);
                }
            },

            mediaFeatures: function () {
                var entities = this.entities, features = [], e;
                do {
                    e = this.mediaFeature();
                    if (e) {
                        features.push(e);
                        if (!$char(',')) {
                            break;
                        }
                    } else {
                        e = entities.variable();
                        if (e) {
                            features.push(e);
                            if (!$char(',')) {
                                break;
                            }
                        }
                    }
                } while (e);

                return features.length > 0 ? features : null;
            },

            media: function () {
                var features, rules, media, debugInfo;

                if (env.dumpLineNumbers) {
                    debugInfo = getDebugInfo(i, input, env);
                }

                if ($re(/^@media/)) {
                    features = this.mediaFeatures();

                    rules = this.block();
                    if (rules) {
                        media = new (tree.Media)(rules, features, i, env.currentFileInfo);
                        if (env.dumpLineNumbers) {
                            media.debugInfo = debugInfo;
                        }
                        return media;
                    }
                }
            },

            //
            // A CSS Directive
            //
            //     @charset "utf-8";
            //
            directive: function () {
                var index = i, name, value, rules, nonVendorSpecificName,
                    hasIdentifier, hasExpression, hasUnknown, hasBlock = true;

                if (input.charAt(i) !== '@') {
                    return;
                }

                value = this['import']() || this.media();
                if (value) {
                    return value;
                }

                save();

                name = $re(/^@[a-z-]+/);

                if (!name) {
                    return;
                }

                nonVendorSpecificName = name;
                if (name.charAt(1) == '-' && name.indexOf('-', 2) > 0) {
                    nonVendorSpecificName = "@" + name.slice(name.indexOf('-', 2) + 1);
                }

                switch (nonVendorSpecificName) {
                    /*
                     case "@font-face":
                     case "@viewport":
                     case "@top-left":
                     case "@top-left-corner":
                     case "@top-center":
                     case "@top-right":
                     case "@top-right-corner":
                     case "@bottom-left":
                     case "@bottom-left-corner":
                     case "@bottom-center":
                     case "@bottom-right":
                     case "@bottom-right-corner":
                     case "@left-top":
                     case "@left-middle":
                     case "@left-bottom":
                     case "@right-top":
                     case "@right-middle":
                     case "@right-bottom":
                     hasBlock = true;
                     break;
                     */
                    case "@charset":
                        hasIdentifier = true;
                        hasBlock = false;
                        break;
                    case "@namespace":
                        hasExpression = true;
                        hasBlock = false;
                        break;
                    case "@keyframes":
                        hasIdentifier = true;
                        break;
                    case "@host":
                    case "@page":
                    case "@document":
                    case "@supports":
                        hasUnknown = true;
                        break;
                }

                this.comments();

                if (hasIdentifier) {
                    value = this.entity();
                    if (!value) {
                        error("expected " + name + " identifier");
                    }
                } else if (hasExpression) {
                    value = this.expression();
                    if (!value) {
                        error("expected " + name + " expression");
                    }
                } else if (hasUnknown) {
                    value = ($re(/^[^{;]+/) || '').trim();
                    if (value) {
                        value = new (tree.Anonymous)(value);
                    }
                }

                this.comments();

                if (hasBlock) {
                    rules = this.blockRuleset();
                }

                if (rules || (!hasBlock && value && $char(';'))) {
                    forget();
                    return new (tree.Directive)(name, value, rules, index, env.currentFileInfo,
                        env.dumpLineNumbers ? getDebugInfo(index, input, env) : null);
                }

                restore();
            },

            //
            // A Value is a comma-delimited list of Expressions
            //
            //     font-family: Baskerville, Georgia, serif;
            //
            // In a Rule, a Value represents everything after the `:`,
            // and before the `;`.
            //
            value: function () {
                var e, expressions = [];

                do {
                    e = this.expression();
                    if (e) {
                        expressions.push(e);
                        if (!$char(',')) {
                            break;
                        }
                    }
                } while (e);

                if (expressions.length > 0) {
                    return new (tree.Value)(expressions);
                }
            },
            important: function () {
                if (input.charAt(i) === '!') {
                    return $re(/^! *important/);
                }
            },
            sub: function () {
                var a, e;

                if ($char('(')) {
                    a = this.addition();
                    if (a) {
                        e = new (tree.Expression)([a]);
                        expectChar(')');
                        e.parens = true;
                        return e;
                    }
                }
            },
            multiplication: function () {
                var m, a, op, operation, isSpaced;
                m = this.operand();
                if (m) {
                    isSpaced = isWhitespace(input, i - 1);
                    while (true) {
                        if (peek(/^\/[*\/]/)) {
                            break;
                        }

                        save();

                        op = $char('/') || $char('*');

                        if (!op) {
                            forget();
                            break;
                        }

                        a = this.operand();

                        if (!a) {
                            restore();
                            break;
                        }
                        forget();

                        m.parensInOp = true;
                        a.parensInOp = true;
                        operation = new (tree.Operation)(op, [operation || m, a], isSpaced);
                        isSpaced = isWhitespace(input, i - 1);
                    }
                    return operation || m;
                }
            },
            addition: function () {
                var m, a, op, operation, isSpaced;
                m = this.multiplication();
                if (m) {
                    isSpaced = isWhitespace(input, i - 1);
                    while (true) {
                        op = $re(/^[-+]\s+/) || (!isSpaced && ($char('+') || $char('-')));
                        if (!op) {
                            break;
                        }
                        a = this.multiplication();
                        if (!a) {
                            break;
                        }

                        m.parensInOp = true;
                        a.parensInOp = true;
                        operation = new (tree.Operation)(op, [operation || m, a], isSpaced);
                        isSpaced = isWhitespace(input, i - 1);
                    }
                    return operation || m;
                }
            },
            conditions: function () {
                var a, b, index = i, condition;

                a = this.condition();
                if (a) {
                    while (true) {
                        if (!peek(/^,\s*(not\s*)?\(/) || !$char(',')) {
                            break;
                        }
                        b = this.condition();
                        if (!b) {
                            break;
                        }
                        condition = new (tree.Condition)('or', condition || a, b, index);
                    }
                    return condition || a;
                }
            },
            condition: function () {
                var entities = this.entities, index = i, negate = false,
                    a, b, c, op;

                if ($re(/^not/)) {
                    negate = true;
                }
                expectChar('(');
                a = this.addition() || entities.keyword() || entities.quoted();
                if (a) {
                    op = $re(/^(?:>=|<=|=<|[<=>])/);
                    if (op) {
                        b = this.addition() || entities.keyword() || entities.quoted();
                        if (b) {
                            c = new (tree.Condition)(op, a, b, index, negate);
                        } else {
                            error('expected expression');
                        }
                    } else {
                        c = new (tree.Condition)('=', a, new (tree.Keyword)('true'), index, negate);
                    }
                    expectChar(')');
                    return $re(/^and/) ? new (tree.Condition)('and', c, this.condition()) : c;
                }
            },

            //
            // An operand is anything that can be part of an operation,
            // such as a Color, or a Variable
            //
            operand: function () {
                var entities = this.entities,
                    p = input.charAt(i + 1), negate;

                if (input.charAt(i) === '-' && (p === '@' || p === '(')) {
                    negate = $char('-');
                }
                var o = this.sub() || entities.dimension() ||
                    entities.color() || entities.variable() ||
                    entities.call();

                if (negate) {
                    o.parensInOp = true;
                    o = new (tree.Negative)(o);
                }

                return o;
            },

            //
            // Expressions either represent mathematical operations,
            // or white-space delimited Entities.
            //
            //     1px solid black
            //     @var * 2
            //
            expression: function () {
                var entities = [], e, delim;

                do {
                    e = this.addition() || this.entity();
                    if (e) {
                        entities.push(e);
                        // operations do not allow keyword "/" dimension (e.g. small/20px) so we support that here
                        if (!peek(/^\/[\/*]/)) {
                            delim = $char('/');
                            if (delim) {
                                entities.push(new (tree.Anonymous)(delim));
                            }
                        }
                    }
                } while (e);
                if (entities.length > 0) {
                    return new (tree.Expression)(entities);
                }
            },
            property: function () {
                var name = $re(/^(\*?-?[_a-zA-Z0-9-]+)\s*:/);
                if (name) {
                    return name[1];
                }
            },
            ruleProperty: function () {
                var c = current, name = [], index = [], length = 0, s, k;

                function match(re) {
                    var a = re.exec(c);
                    if (a) {
                        index.push(i + length);
                        length += a[0].length;
                        c = c.slice(a[1].length);
                        return name.push(a[1]);
                    }
                }

                function cutOutBlockComments() {
                    //match block comments
                    var a = /^\s*\/\*(?:[^*]|\*+[^\/*])*\*+\//.exec(c);
                    if (a) {
                        length += a[0].length;
                        c = c.slice(a[0].length);
                        return true;
                    }
                    return false;
                }

                match(/^(\*?)/);
                while (match(/^((?:[\w-]+)|(?:@\{[\w-]+\}))/)); // !
                while (cutOutBlockComments());
                if ((name.length > 1) && match(/^\s*((?:\+_|\+)?)\s*:/)) {
                    // at last, we have the complete match now. move forward,
                    // convert name particles to tree objects and return:
                    skipWhitespace(length);
                    if (name[0] === '') {
                        name.shift();
                        index.shift();
                    }
                    for (k = 0; k < name.length; k++) {
                        s = name[k];
                        name[k] = (s.charAt(0) !== '@')
                            ? new (tree.Keyword)(s)
                            : new (tree.Variable)('@' + s.slice(2, -1),
                            index[k], env.currentFileInfo);
                    }
                    return name;
                }
            }
        }
    };
    return parser;
};
less.Parser.serializeVars = function (vars) {
    var s = '';

    for (var name in vars) {
        if (Object.hasOwnProperty.call(vars, name)) {
            var value = vars[name];
            s += ((name[0] === '@') ? '' : '@') + name + ': ' + value +
            ((('' + value).slice(-1) === ';') ? '' : ';');
        }
    }

    return s;
};

(function (tree) {

    tree.functions = {
        rgb: function (r, g, b) {
            return this.rgba(r, g, b, 1.0);
        },
        rgba: function (r, g, b, a) {
            var rgb = [r, g, b].map(function (c) {
                return scaled(c, 255);
            });
            a = number(a);
            return new (tree.Color)(rgb, a);
        },
        hsl: function (h, s, l) {
            return this.hsla(h, s, l, 1.0);
        },
        hsla: function (h, s, l, a) {
            function hue(h) {
                h = h < 0 ? h + 1 : (h > 1 ? h - 1 : h);
                if (h * 6 < 1) {
                    return m1 + (m2 - m1) * h * 6;
                }
                else if (h * 2 < 1) {
                    return m2;
                }
                else if (h * 3 < 2) {
                    return m1 + (m2 - m1) * (2 / 3 - h) * 6;
                }
                else {
                    return m1;
                }
            }

            h = (number(h) % 360) / 360;
            s = clamp(number(s));
            l = clamp(number(l));
            a = clamp(number(a));

            var m2 = l <= 0.5 ? l * (s + 1) : l + s - l * s;
            var m1 = l * 2 - m2;

            return this.rgba(hue(h + 1 / 3) * 255,
                hue(h) * 255,
                hue(h - 1 / 3) * 255,
                a);
        },

        hsv: function (h, s, v) {
            return this.hsva(h, s, v, 1.0);
        },

        hsva: function (h, s, v, a) {
            h = ((number(h) % 360) / 360) * 360;
            s = number(s);
            v = number(v);
            a = number(a);

            var i, f;
            i = Math.floor((h / 60) % 6);
            f = (h / 60) - i;

            var vs = [v,
                v * (1 - s),
                v * (1 - f * s),
                v * (1 - (1 - f) * s)];
            var perm = [[0, 3, 1],
                [2, 0, 1],
                [1, 0, 3],
                [1, 2, 0],
                [3, 1, 0],
                [0, 1, 2]];

            return this.rgba(vs[perm[i][0]] * 255,
                vs[perm[i][1]] * 255,
                vs[perm[i][2]] * 255,
                a);
        },

        hue: function (color) {
            return new (tree.Dimension)(color.toHSL().h);
        },
        saturation: function (color) {
            return new (tree.Dimension)(color.toHSL().s * 100, '%');
        },
        lightness: function (color) {
            return new (tree.Dimension)(color.toHSL().l * 100, '%');
        },
        hsvhue: function (color) {
            return new (tree.Dimension)(color.toHSV().h);
        },
        hsvsaturation: function (color) {
            return new (tree.Dimension)(color.toHSV().s * 100, '%');
        },
        hsvvalue: function (color) {
            return new (tree.Dimension)(color.toHSV().v * 100, '%');
        },
        red: function (color) {
            return new (tree.Dimension)(color.rgb[0]);
        },
        green: function (color) {
            return new (tree.Dimension)(color.rgb[1]);
        },
        blue: function (color) {
            return new (tree.Dimension)(color.rgb[2]);
        },
        alpha: function (color) {
            return new (tree.Dimension)(color.toHSL().a);
        },
        luma: function (color) {
            return new (tree.Dimension)(color.luma() * color.alpha * 100, '%');
        },
        luminance: function (color) {
            var luminance =
                (0.2126 * color.rgb[0] / 255)
                + (0.7152 * color.rgb[1] / 255)
                + (0.0722 * color.rgb[2] / 255);

            return new (tree.Dimension)(luminance * color.alpha * 100, '%');
        },
        saturate: function (color, amount) {
            // filter: saturate(3.2);
            // should be kept as is, so check for color
            if (!color.rgb) {
                return null;
            }
            var hsl = color.toHSL();

            hsl.s += amount.value / 100;
            hsl.s = clamp(hsl.s);
            return hsla(hsl);
        },
        desaturate: function (color, amount) {
            var hsl = color.toHSL();

            hsl.s -= amount.value / 100;
            hsl.s = clamp(hsl.s);
            return hsla(hsl);
        },
        lighten: function (color, amount) {
            var hsl = color.toHSL();

            hsl.l += amount.value / 100;
            hsl.l = clamp(hsl.l);
            return hsla(hsl);
        },
        darken: function (color, amount) {
            var hsl = color.toHSL();

            hsl.l -= amount.value / 100;
            hsl.l = clamp(hsl.l);
            return hsla(hsl);
        },
        fadein: function (color, amount) {
            var hsl = color.toHSL();

            hsl.a += amount.value / 100;
            hsl.a = clamp(hsl.a);
            return hsla(hsl);
        },
        fadeout: function (color, amount) {
            var hsl = color.toHSL();

            hsl.a -= amount.value / 100;
            hsl.a = clamp(hsl.a);
            return hsla(hsl);
        },
        fade: function (color, amount) {
            var hsl = color.toHSL();

            hsl.a = amount.value / 100;
            hsl.a = clamp(hsl.a);
            return hsla(hsl);
        },
        spin: function (color, amount) {
            var hsl = color.toHSL();
            var hue = (hsl.h + amount.value) % 360;

            hsl.h = hue < 0 ? 360 + hue : hue;

            return hsla(hsl);
        },
        //
        // Copyright (c) 2006-2009 Hampton Catlin, Nathan Weizenbaum, and Chris Eppstein
        // http://sass-lang.com
        //
        mix: function (color1, color2, weight) {
            if (!weight) {
                weight = new (tree.Dimension)(50);
            }
            var p = weight.value / 100.0;
            var w = p * 2 - 1;
            var a = color1.toHSL().a - color2.toHSL().a;

            var w1 = (((w * a == -1) ? w : (w + a) / (1 + w * a)) + 1) / 2.0;
            var w2 = 1 - w1;

            var rgb = [color1.rgb[0] * w1 + color2.rgb[0] * w2,
                color1.rgb[1] * w1 + color2.rgb[1] * w2,
                color1.rgb[2] * w1 + color2.rgb[2] * w2];

            var alpha = color1.alpha * p + color2.alpha * (1 - p);

            return new (tree.Color)(rgb, alpha);
        },
        greyscale: function (color) {
            return this.desaturate(color, new (tree.Dimension)(100));
        },
        contrast: function (color, dark, light, threshold) {
            // filter: contrast(3.2);
            // should be kept as is, so check for color
            if (!color.rgb) {
                return null;
            }
            if (typeof light === 'undefined') {
                light = this.rgba(255, 255, 255, 1.0);
            }
            if (typeof dark === 'undefined') {
                dark = this.rgba(0, 0, 0, 1.0);
            }
            //Figure out which is actually light and dark!
            if (dark.luma() > light.luma()) {
                var t = light;
                light = dark;
                dark = t;
            }
            if (typeof threshold === 'undefined') {
                threshold = 0.43;
            } else {
                threshold = number(threshold);
            }
            if (color.luma() < threshold) {
                return light;
            } else {
                return dark;
            }
        },
        e: function (str) {
            return new (tree.Anonymous)(str instanceof tree.JavaScript ? str.evaluated : str.value);
        },
        escape: function (str) {
            return new (tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
        },
        replace: function (string, pattern, replacement, flags) {
            var result = string.value;

            result = result.replace(new RegExp(pattern.value, flags ? flags.value : ''), replacement.value);
            return new (tree.Quoted)(string.quote || '', result, string.escaped);
        },
        '%': function (string /* arg, arg, ...*/) {
            var args = Array.prototype.slice.call(arguments, 1),
                result = string.value;

            for (var i = 0; i < args.length; i++) {
                /*jshint loopfunc:true */
                result = result.replace(/%[sda]/i, function (token) {
                    var value = token.match(/s/i) ? args[i].value : args[i].toCSS();
                    return token.match(/[A-Z]$/) ? encodeURIComponent(value) : value;
                });
            }
            result = result.replace(/%%/g, '%');
            return new (tree.Quoted)(string.quote || '', result, string.escaped);
        },
        unit: function (val, unit) {
            if (!(val instanceof tree.Dimension)) {
                throw {
                    type: "Argument",
                    message: "the first argument to unit must be a number" + (val instanceof tree.Operation ? ". Have you forgotten parenthesis?" : "")
                };
            }
            if (unit) {
                if (unit instanceof tree.Keyword) {
                    unit = unit.value;
                } else {
                    unit = unit.toCSS();
                }
            } else {
                unit = "";
            }
            return new (tree.Dimension)(val.value, unit);
        },
        convert: function (val, unit) {
            return val.convertTo(unit.value);
        },
        round: function (n, f) {
            var fraction = typeof(f) === "undefined" ? 0 : f.value;
            return _math(function (num) {
                return num.toFixed(fraction);
            }, null, n);
        },
        pi: function () {
            return new (tree.Dimension)(Math.PI);
        },
        mod: function (a, b) {
            return new (tree.Dimension)(a.value % b.value, a.unit);
        },
        pow: function (x, y) {
            if (typeof x === "number" && typeof y === "number") {
                x = new (tree.Dimension)(x);
                y = new (tree.Dimension)(y);
            } else if (!(x instanceof tree.Dimension) || !(y instanceof tree.Dimension)) {
                throw {type: "Argument", message: "arguments must be numbers"};
            }

            return new (tree.Dimension)(Math.pow(x.value, y.value), x.unit);
        },
        _minmax: function (isMin, args) {
            args = Array.prototype.slice.call(args);
            switch (args.length) {
                case 0:
                    throw {type: "Argument", message: "one or more arguments required"};
            }
            var i, j, current, currentUnified, referenceUnified, unit, unitStatic, unitClone,
                order = [], // elems only contains original argument values.
                values = {}; // key is the unit.toString() for unified tree.Dimension values,
                             // value is the index into the order array.
            for (i = 0; i < args.length; i++) {
                current = args[i];
                if (!(current instanceof tree.Dimension)) {
                    if (Array.isArray(args[i].value)) {
                        Array.prototype.push.apply(args, Array.prototype.slice.call(args[i].value));
                    }
                    continue;
                }
                currentUnified = current.unit.toString() === "" && unitClone !== undefined ? new (tree.Dimension)(current.value, unitClone).unify() : current.unify();
                unit = currentUnified.unit.toString() === "" && unitStatic !== undefined ? unitStatic : currentUnified.unit.toString();
                unitStatic = unit !== "" && unitStatic === undefined || unit !== "" && order[0].unify().unit.toString() === "" ? unit : unitStatic;
                unitClone = unit !== "" && unitClone === undefined ? current.unit.toString() : unitClone;
                j = values[""] !== undefined && unit !== "" && unit === unitStatic ? values[""] : values[unit];
                if (j === undefined) {
                    if (unitStatic !== undefined && unit !== unitStatic) {
                        throw{type: "Argument", message: "incompatible types"};
                    }
                    values[unit] = order.length;
                    order.push(current);
                    continue;
                }
                referenceUnified = order[j].unit.toString() === "" && unitClone !== undefined ? new (tree.Dimension)(order[j].value, unitClone).unify() : order[j].unify();
                if (isMin && currentUnified.value < referenceUnified.value ||
                    !isMin && currentUnified.value > referenceUnified.value) {
                    order[j] = current;
                }
            }
            if (order.length == 1) {
                return order[0];
            }
            args = order.map(function (a) {
                return a.toCSS(this.env);
            }).join(this.env.compress ? "," : ", ");
            return new (tree.Anonymous)((isMin ? "min" : "max") + "(" + args + ")");
        },
        min: function () {
            return this._minmax(true, arguments);
        },
        max: function () {
            return this._minmax(false, arguments);
        },
        "get-unit": function (n) {
            return new (tree.Anonymous)(n.unit);
        },
        argb: function (color) {
            return new (tree.Anonymous)(color.toARGB());
        },
        percentage: function (n) {
            return new (tree.Dimension)(n.value * 100, '%');
        },
        color: function (n) {
            if (n instanceof tree.Quoted) {
                var colorCandidate = n.value,
                    returnColor;
                returnColor = tree.Color.fromKeyword(colorCandidate);
                if (returnColor) {
                    return returnColor;
                }
                if (/^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})/.test(colorCandidate)) {
                    return new (tree.Color)(colorCandidate.slice(1));
                }
                throw {type: "Argument", message: "argument must be a color keyword or 3/6 digit hex e.g. #FFF"};
            } else {
                throw {type: "Argument", message: "argument must be a string"};
            }
        },
        iscolor: function (n) {
            return this._isa(n, tree.Color);
        },
        isnumber: function (n) {
            return this._isa(n, tree.Dimension);
        },
        isstring: function (n) {
            return this._isa(n, tree.Quoted);
        },
        iskeyword: function (n) {
            return this._isa(n, tree.Keyword);
        },
        isurl: function (n) {
            return this._isa(n, tree.URL);
        },
        ispixel: function (n) {
            return this.isunit(n, 'px');
        },
        ispercentage: function (n) {
            return this.isunit(n, '%');
        },
        isem: function (n) {
            return this.isunit(n, 'em');
        },
        isunit: function (n, unit) {
            return (n instanceof tree.Dimension) && n.unit.is(unit.value || unit) ? tree.True : tree.False;
        },
        _isa: function (n, Type) {
            return (n instanceof Type) ? tree.True : tree.False;
        },
        tint: function (color, amount) {
            return this.mix(this.rgb(255, 255, 255), color, amount);
        },
        shade: function (color, amount) {
            return this.mix(this.rgb(0, 0, 0), color, amount);
        },
        extract: function (values, index) {
            index = index.value - 1; // (1-based index)
            // handle non-array values as an array of length 1
            // return 'undefined' if index is invalid
            return Array.isArray(values.value)
                ? values.value[index] : Array(values)[index];
        },
        length: function (values) {
            var n = Array.isArray(values.value) ? values.value.length : 1;
            return new tree.Dimension(n);
        },

        "data-uri": function (mimetypeNode, filePathNode) {

            if (typeof window !== 'undefined') {
                return new tree.URL(filePathNode || mimetypeNode, this.currentFileInfo).eval(this.env);
            }

            var mimetype = mimetypeNode.value;
            var filePath = (filePathNode && filePathNode.value);

            var fs = require('./fs'),
                path = require('path'),
                useBase64 = false;

            if (arguments.length < 2) {
                filePath = mimetype;
            }

            var fragmentStart = filePath.indexOf('#');
            var fragment = '';
            if (fragmentStart !== -1) {
                fragment = filePath.slice(fragmentStart);
                filePath = filePath.slice(0, fragmentStart);
            }

            if (this.env.isPathRelative(filePath)) {
                if (this.currentFileInfo.relativeUrls) {
                    filePath = path.join(this.currentFileInfo.currentDirectory, filePath);
                } else {
                    filePath = path.join(this.currentFileInfo.entryPath, filePath);
                }
            }

            // detect the mimetype if not given
            if (arguments.length < 2) {
                var mime;
                try {
                    mime = require('mime');
                } catch (ex) {
                    mime = tree._mime;
                }

                mimetype = mime.lookup(filePath);

                // use base 64 unless it's an ASCII or UTF-8 format
                var charset = mime.charsets.lookup(mimetype);
                useBase64 = ['US-ASCII', 'UTF-8'].indexOf(charset) < 0;
                if (useBase64) {
                    mimetype += ';base64';
                }
            }
            else {
                useBase64 = /;base64$/.test(mimetype);
            }

            var buf = fs.readFileSync(filePath);

            // IE8 cannot handle a data-uri larger than 32KB. If this is exceeded
            // and the --ieCompat flag is enabled, return a normal url() instead.
            var DATA_URI_MAX_KB = 32,
                fileSizeInKB = parseInt((buf.length / 1024), 10);
            if (fileSizeInKB >= DATA_URI_MAX_KB) {

                if (this.env.ieCompat !== false) {
                    if (!this.env.silent) {
                        console.warn("Skipped data-uri embedding of %s because its size (%dKB) exceeds IE8-safe %dKB!", filePath, fileSizeInKB, DATA_URI_MAX_KB);
                    }

                    return new tree.URL(filePathNode || mimetypeNode, this.currentFileInfo).eval(this.env);
                }
            }

            buf = useBase64 ? buf.toString('base64')
                : encodeURIComponent(buf);

            var uri = "\"data:" + mimetype + ',' + buf + fragment + "\"";
            return new (tree.URL)(new (tree.Anonymous)(uri));
        },

        "svg-gradient": function (direction) {

            function throwArgumentDescriptor() {
                throw {
                    type: "Argument",
                    message: "svg-gradient expects direction, start_color [start_position], [color position,]..., end_color [end_position]"
                };
            }

            if (arguments.length < 3) {
                throwArgumentDescriptor();
            }
            var stops = Array.prototype.slice.call(arguments, 1),
                gradientDirectionSvg,
                gradientType = "linear",
                rectangleDimension = 'x="0" y="0" width="1" height="1"',
                useBase64 = true,
                renderEnv = {compress: false},
                returner,
                directionValue = direction.toCSS(renderEnv),
                i, color, position, positionValue, alpha;

            switch (directionValue) {
                case "to bottom":
                    gradientDirectionSvg = 'x1="0%" y1="0%" x2="0%" y2="100%"';
                    break;
                case "to right":
                    gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="0%"';
                    break;
                case "to bottom right":
                    gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="100%"';
                    break;
                case "to top right":
                    gradientDirectionSvg = 'x1="0%" y1="100%" x2="100%" y2="0%"';
                    break;
                case "ellipse":
                case "ellipse at center":
                    gradientType = "radial";
                    gradientDirectionSvg = 'cx="50%" cy="50%" r="75%"';
                    rectangleDimension = 'x="-50" y="-50" width="101" height="101"';
                    break;
                default:
                    throw {
                        type: "Argument",
                        message: "svg-gradient direction must be 'to bottom', 'to right', 'to bottom right', 'to top right' or 'ellipse at center'"
                    };
            }
            returner = '<?xml version="1.0" ?>' +
            '<svg xmlns="http://www.w3.org/2000/svg" version="1.1" width="100%" height="100%" viewBox="0 0 1 1" preserveAspectRatio="none">' +
            '<' + gradientType + 'Gradient id="gradient" gradientUnits="userSpaceOnUse" ' + gradientDirectionSvg + '>';

            for (i = 0; i < stops.length; i += 1) {
                if (stops[i].value) {
                    color = stops[i].value[0];
                    position = stops[i].value[1];
                } else {
                    color = stops[i];
                    position = undefined;
                }

                if (!(color instanceof tree.Color) || (!((i === 0 || i + 1 === stops.length) && position === undefined) && !(position instanceof tree.Dimension))) {
                    throwArgumentDescriptor();
                }
                positionValue = position ? position.toCSS(renderEnv) : i === 0 ? "0%" : "100%";
                alpha = color.alpha;
                returner += '<stop offset="' + positionValue + '" stop-color="' + color.toRGB() + '"' + (alpha < 1 ? ' stop-opacity="' + alpha + '"' : '') + '/>';
            }
            returner += '</' + gradientType + 'Gradient>' +
            '<rect ' + rectangleDimension + ' fill="url(#gradient)" /></svg>';

            if (useBase64) {
                try {
                    returner = require('./encoder').encodeBase64(returner); // TODO browser implementation
                } catch (e) {
                    useBase64 = false;
                }
            }

            returner = "'data:image/svg+xml" + (useBase64 ? ";base64" : "") + "," + returner + "'";
            return new (tree.URL)(new (tree.Anonymous)(returner));
        }
    };

// these static methods are used as a fallback when the optional 'mime' dependency is missing
    tree._mime = {
        // this map is intentionally incomplete
        // if you want more, install 'mime' dep
        _types: {
            '.htm': 'text/html',
            '.html': 'text/html',
            '.gif': 'image/gif',
            '.jpg': 'image/jpeg',
            '.jpeg': 'image/jpeg',
            '.png': 'image/png'
        },
        lookup: function (filepath) {
            var ext = require('path').extname(filepath),
                type = tree._mime._types[ext];
            if (type === undefined) {
                throw new Error('Optional dependency "mime" is required for ' + ext);
            }
            return type;
        },
        charsets: {
            lookup: function (type) {
                // assumes all text types are UTF-8
                return type && (/^text\//).test(type) ? 'UTF-8' : '';
            }
        }
    };

// Math

    var mathFunctions = {
        // name,  unit
        ceil: null,
        floor: null,
        sqrt: null,
        abs: null,
        tan: "",
        sin: "",
        cos: "",
        atan: "rad",
        asin: "rad",
        acos: "rad"
    };

    function _math(fn, unit, n) {
        if (!(n instanceof tree.Dimension)) {
            throw {type: "Argument", message: "argument must be a number"};
        }
        if (unit == null) {
            unit = n.unit;
        } else {
            n = n.unify();
        }
        return new (tree.Dimension)(fn(parseFloat(n.value)), unit);
    }

// ~ End of Math

// Color Blending
// ref: http://www.w3.org/TR/compositing-1

    function colorBlend(mode, color1, color2) {
        var ab = color1.alpha, cb, // backdrop
            as = color2.alpha, cs, // source
            ar, cr, r = [];        // result

        ar = as + ab * (1 - as);
        for (var i = 0; i < 3; i++) {
            cb = color1.rgb[i] / 255;
            cs = color2.rgb[i] / 255;
            cr = mode(cb, cs);
            if (ar) {
                cr = (as * cs + ab * (cb
                - as * (cb + cs - cr))) / ar;
            }
            r[i] = cr * 255;
        }

        return new (tree.Color)(r, ar);
    }

    var colorBlendMode = {
        multiply: function (cb, cs) {
            return cb * cs;
        },
        screen: function (cb, cs) {
            return cb + cs - cb * cs;
        },
        overlay: function (cb, cs) {
            cb *= 2;
            return (cb <= 1)
                ? colorBlendMode.multiply(cb, cs)
                : colorBlendMode.screen(cb - 1, cs);
        },
        softlight: function (cb, cs) {
            var d = 1, e = cb;
            if (cs > 0.5) {
                e = 1;
                d = (cb > 0.25) ? Math.sqrt(cb)
                    : ((16 * cb - 12) * cb + 4) * cb;
            }
            return cb - (1 - 2 * cs) * e * (d - cb);
        },
        hardlight: function (cb, cs) {
            return colorBlendMode.overlay(cs, cb);
        },
        difference: function (cb, cs) {
            return Math.abs(cb - cs);
        },
        exclusion: function (cb, cs) {
            return cb + cs - 2 * cb * cs;
        },

        // non-w3c functions:
        average: function (cb, cs) {
            return (cb + cs) / 2;
        },
        negation: function (cb, cs) {
            return 1 - Math.abs(cb + cs - 1);
        }
    };

// ~ End of Color Blending

    tree.defaultFunc = {
        eval: function () {
            var v = this.value_, e = this.error_;
            if (e) {
                throw e;
            }
            if (v != null) {
                return v ? tree.True : tree.False;
            }
        },
        value: function (v) {
            this.value_ = v;
        },
        error: function (e) {
            this.error_ = e;
        },
        reset: function () {
            this.value_ = this.error_ = null;
        }
    };

    function initFunctions() {
        var f, tf = tree.functions;

        // math
        for (f in mathFunctions) {
            if (mathFunctions.hasOwnProperty(f)) {
                tf[f] = _math.bind(null, Math[f], mathFunctions[f]);
            }
        }

        // color blending
        for (f in colorBlendMode) {
            if (colorBlendMode.hasOwnProperty(f)) {
                tf[f] = colorBlend.bind(null, colorBlendMode[f]);
            }
        }

        // default
        f = tree.defaultFunc;
        tf["default"] = f.eval.bind(f);

    }

    initFunctions();

    function hsla(color) {
        return tree.functions.hsla(color.h, color.s, color.l, color.a);
    }

    function scaled(n, size) {
        if (n instanceof tree.Dimension && n.unit.is('%')) {
            return parseFloat(n.value * size / 100);
        } else {
            return number(n);
        }
    }

    function number(n) {
        if (n instanceof tree.Dimension) {
            return parseFloat(n.unit.is('%') ? n.value / 100 : n.value);
        } else if (typeof(n) === 'number') {
            return n;
        } else {
            throw {
                error: "RuntimeError",
                message: "color functions take numbers as parameters"
            };
        }
    }

    function clamp(val) {
        return Math.min(1, Math.max(0, val));
    }

    tree.fround = function (env, value) {
        var p = env && env.numPrecision;
        //add "epsilon" to ensure numbers like 1.000000005 (represented as 1.000000004999....) are properly rounded...
        return (p == null) ? value : Number((value + 2e-16).toFixed(p));
    };

    tree.functionCall = function (env, currentFileInfo) {
        this.env = env;
        this.currentFileInfo = currentFileInfo;
    };

    tree.functionCall.prototype = tree.functions;

})(require('./tree'));

(function (tree) {
    tree.colors = {
        'aliceblue': '#f0f8ff',
        'antiquewhite': '#faebd7',
        'aqua': '#00ffff',
        'aquamarine': '#7fffd4',
        'azure': '#f0ffff',
        'beige': '#f5f5dc',
        'bisque': '#ffe4c4',
        'black': '#000000',
        'blanchedalmond': '#ffebcd',
        'blue': '#0000ff',
        'blueviolet': '#8a2be2',
        'brown': '#a52a2a',
        'burlywood': '#deb887',
        'cadetblue': '#5f9ea0',
        'chartreuse': '#7fff00',
        'chocolate': '#d2691e',
        'coral': '#ff7f50',
        'cornflowerblue': '#6495ed',
        'cornsilk': '#fff8dc',
        'crimson': '#dc143c',
        'cyan': '#00ffff',
        'darkblue': '#00008b',
        'darkcyan': '#008b8b',
        'darkgoldenrod': '#b8860b',
        'darkgray': '#a9a9a9',
        'darkgrey': '#a9a9a9',
        'darkgreen': '#006400',
        'darkkhaki': '#bdb76b',
        'darkmagenta': '#8b008b',
        'darkolivegreen': '#556b2f',
        'darkorange': '#ff8c00',
        'darkorchid': '#9932cc',
        'darkred': '#8b0000',
        'darksalmon': '#e9967a',
        'darkseagreen': '#8fbc8f',
        'darkslateblue': '#483d8b',
        'darkslategray': '#2f4f4f',
        'darkslategrey': '#2f4f4f',
        'darkturquoise': '#00ced1',
        'darkviolet': '#9400d3',
        'deeppink': '#ff1493',
        'deepskyblue': '#00bfff',
        'dimgray': '#696969',
        'dimgrey': '#696969',
        'dodgerblue': '#1e90ff',
        'firebrick': '#b22222',
        'floralwhite': '#fffaf0',
        'forestgreen': '#228b22',
        'fuchsia': '#ff00ff',
        'gainsboro': '#dcdcdc',
        'ghostwhite': '#f8f8ff',
        'gold': '#ffd700',
        'goldenrod': '#daa520',
        'gray': '#808080',
        'grey': '#808080',
        'green': '#008000',
        'greenyellow': '#adff2f',
        'honeydew': '#f0fff0',
        'hotpink': '#ff69b4',
        'indianred': '#cd5c5c',
        'indigo': '#4b0082',
        'ivory': '#fffff0',
        'khaki': '#f0e68c',
        'lavender': '#e6e6fa',
        'lavenderblush': '#fff0f5',
        'lawngreen': '#7cfc00',
        'lemonchiffon': '#fffacd',
        'lightblue': '#add8e6',
        'lightcoral': '#f08080',
        'lightcyan': '#e0ffff',
        'lightgoldenrodyellow': '#fafad2',
        'lightgray': '#d3d3d3',
        'lightgrey': '#d3d3d3',
        'lightgreen': '#90ee90',
        'lightpink': '#ffb6c1',
        'lightsalmon': '#ffa07a',
        'lightseagreen': '#20b2aa',
        'lightskyblue': '#87cefa',
        'lightslategray': '#778899',
        'lightslategrey': '#778899',
        'lightsteelblue': '#b0c4de',
        'lightyellow': '#ffffe0',
        'lime': '#00ff00',
        'limegreen': '#32cd32',
        'linen': '#faf0e6',
        'magenta': '#ff00ff',
        'maroon': '#800000',
        'mediumaquamarine': '#66cdaa',
        'mediumblue': '#0000cd',
        'mediumorchid': '#ba55d3',
        'mediumpurple': '#9370d8',
        'mediumseagreen': '#3cb371',
        'mediumslateblue': '#7b68ee',
        'mediumspringgreen': '#00fa9a',
        'mediumturquoise': '#48d1cc',
        'mediumvioletred': '#c71585',
        'midnightblue': '#191970',
        'mintcream': '#f5fffa',
        'mistyrose': '#ffe4e1',
        'moccasin': '#ffe4b5',
        'navajowhite': '#ffdead',
        'navy': '#000080',
        'oldlace': '#fdf5e6',
        'olive': '#808000',
        'olivedrab': '#6b8e23',
        'orange': '#ffa500',
        'orangered': '#ff4500',
        'orchid': '#da70d6',
        'palegoldenrod': '#eee8aa',
        'palegreen': '#98fb98',
        'paleturquoise': '#afeeee',
        'palevioletred': '#d87093',
        'papayawhip': '#ffefd5',
        'peachpuff': '#ffdab9',
        'peru': '#cd853f',
        'pink': '#ffc0cb',
        'plum': '#dda0dd',
        'powderblue': '#b0e0e6',
        'purple': '#800080',
        'red': '#ff0000',
        'rosybrown': '#bc8f8f',
        'royalblue': '#4169e1',
        'saddlebrown': '#8b4513',
        'salmon': '#fa8072',
        'sandybrown': '#f4a460',
        'seagreen': '#2e8b57',
        'seashell': '#fff5ee',
        'sienna': '#a0522d',
        'silver': '#c0c0c0',
        'skyblue': '#87ceeb',
        'slateblue': '#6a5acd',
        'slategray': '#708090',
        'slategrey': '#708090',
        'snow': '#fffafa',
        'springgreen': '#00ff7f',
        'steelblue': '#4682b4',
        'tan': '#d2b48c',
        'teal': '#008080',
        'thistle': '#d8bfd8',
        'tomato': '#ff6347',
        'turquoise': '#40e0d0',
        'violet': '#ee82ee',
        'wheat': '#f5deb3',
        'white': '#ffffff',
        'whitesmoke': '#f5f5f5',
        'yellow': '#ffff00',
        'yellowgreen': '#9acd32'
    };
})(require('./tree'));

(function (tree) {

    tree.debugInfo = function (env, ctx, lineSeperator) {
        var result = "";
        if (env.dumpLineNumbers && !env.compress) {
            switch (env.dumpLineNumbers) {
                case 'comments':
                    result = tree.debugInfo.asComment(ctx);
                    break;
                case 'mediaquery':
                    result = tree.debugInfo.asMediaQuery(ctx);
                    break;
                case 'all':
                    result = tree.debugInfo.asComment(ctx) + (lineSeperator || "") + tree.debugInfo.asMediaQuery(ctx);
                    break;
            }
        }
        return result;
    };

    tree.debugInfo.asComment = function (ctx) {
        return '/* line ' + ctx.debugInfo.lineNumber + ', ' + ctx.debugInfo.fileName + ' */\n';
    };

    tree.debugInfo.asMediaQuery = function (ctx) {
        return '@media -sass-debug-info{filename{font-family:' +
            ('file://' + ctx.debugInfo.fileName).replace(/([.:\/\\])/g, function (a) {
                if (a == '\\') {
                    a = '\/';
                }
                return '\\' + a;
            }) +
            '}line{font-family:\\00003' + ctx.debugInfo.lineNumber + '}}\n';
    };

    tree.find = function (obj, fun) {
        for (var i = 0, r; i < obj.length; i++) {
            r = fun.call(obj, obj[i]);
            if (r) {
                return r;
            }
        }
        return null;
    };

    tree.jsify = function (obj) {
        if (Array.isArray(obj.value) && (obj.value.length > 1)) {
            return '[' + obj.value.map(function (v) {
                    return v.toCSS();
                }).join(', ') + ']';
        } else {
            return obj.toCSS();
        }
    };

    tree.toCSS = function (env) {
        var strs = [];
        this.genCSS(env, {
            add: function (chunk, fileInfo, index) {
                strs.push(chunk);
            },
            isEmpty: function () {
                return strs.length === 0;
            }
        });
        return strs.join('');
    };

    tree.outputRuleset = function (env, output, rules) {
        var ruleCnt = rules.length, i;
        env.tabLevel = (env.tabLevel | 0) + 1;

        // Compressed
        if (env.compress) {
            output.add('{');
            for (i = 0; i < ruleCnt; i++) {
                rules[i].genCSS(env, output);
            }
            output.add('}');
            env.tabLevel--;
            return;
        }

        // Non-compressed
        var tabSetStr = '\n' + Array(env.tabLevel).join("  "), tabRuleStr = tabSetStr + "  ";
        if (!ruleCnt) {
            output.add(" {" + tabSetStr + '}');
        } else {
            output.add(" {" + tabRuleStr);
            rules[0].genCSS(env, output);
            for (i = 1; i < ruleCnt; i++) {
                output.add(tabRuleStr);
                rules[i].genCSS(env, output);
            }
            output.add(tabSetStr + '}');
        }

        env.tabLevel--;
    };

})(require('./tree'));

(function (tree) {

    tree.Alpha = function (val) {
        this.value = val;
    };
    tree.Alpha.prototype = {
        type: "Alpha",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        eval: function (env) {
            if (this.value.eval) {
                return new tree.Alpha(this.value.eval(env));
            }
            return this;
        },
        genCSS: function (env, output) {
            output.add("alpha(opacity=");

            if (this.value.genCSS) {
                this.value.genCSS(env, output);
            } else {
                output.add(this.value);
            }

            output.add(")");
        },
        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {

    tree.Anonymous = function (value, index, currentFileInfo, mapLines, rulesetLike) {
        this.value = value;
        this.index = index;
        this.mapLines = mapLines;
        this.currentFileInfo = currentFileInfo;
        this.rulesetLike = (typeof rulesetLike === 'undefined') ? false : rulesetLike;
    };
    tree.Anonymous.prototype = {
        type: "Anonymous",
        eval: function () {
            return new tree.Anonymous(this.value, this.index, this.currentFileInfo, this.mapLines, this.rulesetLike);
        },
        compare: function (x) {
            if (!x.toCSS) {
                return -1;
            }

            var left = this.toCSS(),
                right = x.toCSS();

            if (left === right) {
                return 0;
            }

            return left < right ? -1 : 1;
        },
        isRulesetLike: function () {
            return this.rulesetLike;
        },
        genCSS: function (env, output) {
            output.add(this.value, this.currentFileInfo, this.index, this.mapLines);
        },
        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {

    tree.Assignment = function (key, val) {
        this.key = key;
        this.value = val;
    };
    tree.Assignment.prototype = {
        type: "Assignment",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        eval: function (env) {
            if (this.value.eval) {
                return new (tree.Assignment)(this.key, this.value.eval(env));
            }
            return this;
        },
        genCSS: function (env, output) {
            output.add(this.key + '=');
            if (this.value.genCSS) {
                this.value.genCSS(env, output);
            } else {
                output.add(this.value);
            }
        },
        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {

//
// A function call node.
//
    tree.Call = function (name, args, index, currentFileInfo) {
        this.name = name;
        this.args = args;
        this.index = index;
        this.currentFileInfo = currentFileInfo;
    };
    tree.Call.prototype = {
        type: "Call",
        accept: function (visitor) {
            if (this.args) {
                this.args = visitor.visitArray(this.args);
            }
        },
        //
        // When evaluating a function call,
        // we either find the function in `tree.functions` [1],
        // in which case we call it, passing the  evaluated arguments,
        // if this returns null or we cannot find the function, we 
        // simply print it out as it appeared originally [2].
        //
        // The *functions.js* file contains the built-in functions.
        //
        // The reason why we evaluate the arguments, is in the case where
        // we try to pass a variable to a function, like: `saturate(@color)`.
        // The function should receive the value, not the variable.
        //
        eval: function (env) {
            var args = this.args.map(function (a) {
                    return a.eval(env);
                }),
                nameLC = this.name.toLowerCase(),
                result, func;

            if (nameLC in tree.functions) { // 1.
                try {
                    func = new tree.functionCall(env, this.currentFileInfo);
                    result = func[nameLC].apply(func, args);
                    if (result != null) {
                        return result;
                    }
                } catch (e) {
                    throw {
                        type: e.type || "Runtime",
                        message: "error evaluating function `" + this.name + "`" +
                        (e.message ? ': ' + e.message : ''),
                        index: this.index, filename: this.currentFileInfo.filename
                    };
                }
            }

            return new tree.Call(this.name, args, this.index, this.currentFileInfo);
        },

        genCSS: function (env, output) {
            output.add(this.name + "(", this.currentFileInfo, this.index);

            for (var i = 0; i < this.args.length; i++) {
                this.args[i].genCSS(env, output);
                if (i + 1 < this.args.length) {
                    output.add(", ");
                }
            }

            output.add(")");
        },

        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {
//
// RGB Colors - #ff0014, #eee
//
    tree.Color = function (rgb, a) {
        //
        // The end goal here, is to parse the arguments
        // into an integer triplet, such as `128, 255, 0`
        //
        // This facilitates operations and conversions.
        //
        if (Array.isArray(rgb)) {
            this.rgb = rgb;
        } else if (rgb.length == 6) {
            this.rgb = rgb.match(/.{2}/g).map(function (c) {
                return parseInt(c, 16);
            });
        } else {
            this.rgb = rgb.split('').map(function (c) {
                return parseInt(c + c, 16);
            });
        }
        this.alpha = typeof(a) === 'number' ? a : 1;
    };

    var transparentKeyword = "transparent";

    tree.Color.prototype = {
        type: "Color",
        eval: function () {
            return this;
        },
        luma: function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255;

            r = (r <= 0.03928) ? r / 12.92 : Math.pow(((r + 0.055) / 1.055), 2.4);
            g = (g <= 0.03928) ? g / 12.92 : Math.pow(((g + 0.055) / 1.055), 2.4);
            b = (b <= 0.03928) ? b / 12.92 : Math.pow(((b + 0.055) / 1.055), 2.4);

            return 0.2126 * r + 0.7152 * g + 0.0722 * b;
        },

        genCSS: function (env, output) {
            output.add(this.toCSS(env));
        },
        toCSS: function (env, doNotCompress) {
            var compress = env && env.compress && !doNotCompress,
                alpha = tree.fround(env, this.alpha);

            // If we have some transparency, the only way to represent it
            // is via `rgba`. Otherwise, we use the hex representation,
            // which has better compatibility with older browsers.
            // Values are capped between `0` and `255`, rounded and zero-padded.
            if (alpha < 1) {
                if (alpha === 0 && this.isTransparentKeyword) {
                    return transparentKeyword;
                }
                return "rgba(" + this.rgb.map(function (c) {
                        return clamp(Math.round(c), 255);
                    }).concat(clamp(alpha, 1))
                        .join(',' + (compress ? '' : ' ')) + ")";
            } else {
                var color = this.toRGB();

                if (compress) {
                    var splitcolor = color.split('');

                    // Convert color to short format
                    if (splitcolor[1] === splitcolor[2] && splitcolor[3] === splitcolor[4] && splitcolor[5] === splitcolor[6]) {
                        color = '#' + splitcolor[1] + splitcolor[3] + splitcolor[5];
                    }
                }

                return color;
            }
        },

        //
        // Operations have to be done per-channel, if not,
        // channels will spill onto each other. Once we have
        // our result, in the form of an integer triplet,
        // we create a new Color node to hold the result.
        //
        operate: function (env, op, other) {
            var rgb = [];
            var alpha = this.alpha * (1 - other.alpha) + other.alpha;
            for (var c = 0; c < 3; c++) {
                rgb[c] = tree.operate(env, op, this.rgb[c], other.rgb[c]);
            }
            return new (tree.Color)(rgb, alpha);
        },

        toRGB: function () {
            return toHex(this.rgb);
        },

        toHSL: function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;

            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, l = (max + min) / 2, d = max - min;

            if (max === min) {
                h = s = 0;
            } else {
                s = l > 0.5 ? d / (2 - max - min) : d / (max + min);

                switch (max) {
                    case r:
                        h = (g - b) / d + (g < b ? 6 : 0);
                        break;
                    case g:
                        h = (b - r) / d + 2;
                        break;
                    case b:
                        h = (r - g) / d + 4;
                        break;
                }
                h /= 6;
            }
            return {h: h * 360, s: s, l: l, a: a};
        },
        //Adapted from http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript
        toHSV: function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;

            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, v = max;

            var d = max - min;
            if (max === 0) {
                s = 0;
            } else {
                s = d / max;
            }

            if (max === min) {
                h = 0;
            } else {
                switch (max) {
                    case r:
                        h = (g - b) / d + (g < b ? 6 : 0);
                        break;
                    case g:
                        h = (b - r) / d + 2;
                        break;
                    case b:
                        h = (r - g) / d + 4;
                        break;
                }
                h /= 6;
            }
            return {h: h * 360, s: s, v: v, a: a};
        },
        toARGB: function () {
            return toHex([this.alpha * 255].concat(this.rgb));
        },
        compare: function (x) {
            if (!x.rgb) {
                return -1;
            }

            return (x.rgb[0] === this.rgb[0] &&
            x.rgb[1] === this.rgb[1] &&
            x.rgb[2] === this.rgb[2] &&
            x.alpha === this.alpha) ? 0 : -1;
        }
    };

    tree.Color.fromKeyword = function (keyword) {
        keyword = keyword.toLowerCase();

        if (tree.colors.hasOwnProperty(keyword)) {
            // detect named color
            return new (tree.Color)(tree.colors[keyword].slice(1));
        }
        if (keyword === transparentKeyword) {
            var transparent = new (tree.Color)([0, 0, 0], 0);
            transparent.isTransparentKeyword = true;
            return transparent;
        }
    };

    function toHex(v) {
        return '#' + v.map(function (c) {
                c = clamp(Math.round(c), 255);
                return (c < 16 ? '0' : '') + c.toString(16);
            }).join('');
    }

    function clamp(v, max) {
        return Math.min(Math.max(v, 0), max);
    }

})(require('../tree'));

(function (tree) {

    tree.Comment = function (value, silent, index, currentFileInfo) {
        this.value = value;
        this.silent = !!silent;
        this.currentFileInfo = currentFileInfo;
    };
    tree.Comment.prototype = {
        type: "Comment",
        genCSS: function (env, output) {
            if (this.debugInfo) {
                output.add(tree.debugInfo(env, this), this.currentFileInfo, this.index);
            }
            output.add(this.value.trim()); //TODO shouldn't need to trim, we shouldn't grab the \n
        },
        toCSS: tree.toCSS,
        isSilent: function (env) {
            var isReference = (this.currentFileInfo && this.currentFileInfo.reference && !this.isReferenced),
                isCompressed = env.compress && !this.value.match(/^\/\*!/);
            return this.silent || isReference || isCompressed;
        },
        eval: function () {
            return this;
        },
        markReferenced: function () {
            this.isReferenced = true;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Condition = function (op, l, r, i, negate) {
        this.op = op.trim();
        this.lvalue = l;
        this.rvalue = r;
        this.index = i;
        this.negate = negate;
    };
    tree.Condition.prototype = {
        type: "Condition",
        accept: function (visitor) {
            this.lvalue = visitor.visit(this.lvalue);
            this.rvalue = visitor.visit(this.rvalue);
        },
        eval: function (env) {
            var a = this.lvalue.eval(env),
                b = this.rvalue.eval(env);

            var i = this.index, result;

            result = (function (op) {
                switch (op) {
                    case 'and':
                        return a && b;
                    case 'or':
                        return a || b;
                    default:
                        if (a.compare) {
                            result = a.compare(b);
                        } else if (b.compare) {
                            result = b.compare(a);
                        } else {
                            throw {
                                type: "Type",
                                message: "Unable to perform comparison",
                                index: i
                            };
                        }
                        switch (result) {
                            case -1:
                                return op === '<' || op === '=<' || op === '<=';
                            case  0:
                                return op === '=' || op === '>=' || op === '=<' || op === '<=';
                            case  1:
                                return op === '>' || op === '>=';
                        }
                }
            })(this.op);
            return this.negate ? !result : result;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.DetachedRuleset = function (ruleset, frames) {
        this.ruleset = ruleset;
        this.frames = frames;
    };
    tree.DetachedRuleset.prototype = {
        type: "DetachedRuleset",
        accept: function (visitor) {
            this.ruleset = visitor.visit(this.ruleset);
        },
        eval: function (env) {
            var frames = this.frames || env.frames.slice(0);
            return new tree.DetachedRuleset(this.ruleset, frames);
        },
        callEval: function (env) {
            return this.ruleset.eval(this.frames ? new (tree.evalEnv)(env, this.frames.concat(env.frames)) : env);
        }
    };
})(require('../tree'));

(function (tree) {

//
// A number with a unit
//
    tree.Dimension = function (value, unit) {
        this.value = parseFloat(value);
        this.unit = (unit && unit instanceof tree.Unit) ? unit :
            new (tree.Unit)(unit ? [unit] : undefined);
    };

    tree.Dimension.prototype = {
        type: "Dimension",
        accept: function (visitor) {
            this.unit = visitor.visit(this.unit);
        },
        eval: function (env) {
            return this;
        },
        toColor: function () {
            return new (tree.Color)([this.value, this.value, this.value]);
        },
        genCSS: function (env, output) {
            if ((env && env.strictUnits) && !this.unit.isSingular()) {
                throw new Error("Multiple units in dimension. Correct the units or use the unit function. Bad unit: " + this.unit.toString());
            }

            var value = tree.fround(env, this.value),
                strValue = String(value);

            if (value !== 0 && value < 0.000001 && value > -0.000001) {
                // would be output 1e-6 etc.
                strValue = value.toFixed(20).replace(/0+$/, "");
            }

            if (env && env.compress) {
                // Zero values doesn't need a unit
                if (value === 0 && this.unit.isLength()) {
                    output.add(strValue);
                    return;
                }

                // Float values doesn't need a leading zero
                if (value > 0 && value < 1) {
                    strValue = (strValue).substr(1);
                }
            }

            output.add(strValue);
            this.unit.genCSS(env, output);
        },
        toCSS: tree.toCSS,

        // In an operation between two Dimensions,
        // we default to the first Dimension's unit,
        // so `1px + 2` will yield `3px`.
        operate: function (env, op, other) {
            /*jshint noempty:false */
            var value = tree.operate(env, op, this.value, other.value),
                unit = this.unit.clone();

            if (op === '+' || op === '-') {
                if (unit.numerator.length === 0 && unit.denominator.length === 0) {
                    unit.numerator = other.unit.numerator.slice(0);
                    unit.denominator = other.unit.denominator.slice(0);
                } else if (other.unit.numerator.length === 0 && unit.denominator.length === 0) {
                    // do nothing
                } else {
                    other = other.convertTo(this.unit.usedUnits());

                    if (env.strictUnits && other.unit.toString() !== unit.toString()) {
                        throw new Error("Incompatible units. Change the units or use the unit function. Bad units: '" + unit.toString() +
                        "' and '" + other.unit.toString() + "'.");
                    }

                    value = tree.operate(env, op, this.value, other.value);
                }
            } else if (op === '*') {
                unit.numerator = unit.numerator.concat(other.unit.numerator).sort();
                unit.denominator = unit.denominator.concat(other.unit.denominator).sort();
                unit.cancel();
            } else if (op === '/') {
                unit.numerator = unit.numerator.concat(other.unit.denominator).sort();
                unit.denominator = unit.denominator.concat(other.unit.numerator).sort();
                unit.cancel();
            }
            return new (tree.Dimension)(value, unit);
        },

        compare: function (other) {
            if (other instanceof tree.Dimension) {
                var a, b,
                    aValue, bValue;

                if (this.unit.isEmpty() || other.unit.isEmpty()) {
                    a = this;
                    b = other;
                } else {
                    a = this.unify();
                    b = other.unify();
                    if (a.unit.compare(b.unit) !== 0) {
                        return -1;
                    }
                }
                aValue = a.value;
                bValue = b.value;

                if (bValue > aValue) {
                    return -1;
                } else if (bValue < aValue) {
                    return 1;
                } else {
                    return 0;
                }
            } else {
                return -1;
            }
        },

        unify: function () {
            return this.convertTo({length: 'px', duration: 's', angle: 'rad'});
        },

        convertTo: function (conversions) {
            var value = this.value, unit = this.unit.clone(),
                i, groupName, group, targetUnit, derivedConversions = {}, applyUnit;

            if (typeof conversions === 'string') {
                for (i in tree.UnitConversions) {
                    if (tree.UnitConversions[i].hasOwnProperty(conversions)) {
                        derivedConversions = {};
                        derivedConversions[i] = conversions;
                    }
                }
                conversions = derivedConversions;
            }
            applyUnit = function (atomicUnit, denominator) {
                /*jshint loopfunc:true */
                if (group.hasOwnProperty(atomicUnit)) {
                    if (denominator) {
                        value = value / (group[atomicUnit] / group[targetUnit]);
                    } else {
                        value = value * (group[atomicUnit] / group[targetUnit]);
                    }

                    return targetUnit;
                }

                return atomicUnit;
            };

            for (groupName in conversions) {
                if (conversions.hasOwnProperty(groupName)) {
                    targetUnit = conversions[groupName];
                    group = tree.UnitConversions[groupName];

                    unit.map(applyUnit);
                }
            }

            unit.cancel();

            return new (tree.Dimension)(value, unit);
        }
    };

// http://www.w3.org/TR/css3-values/#absolute-lengths
    tree.UnitConversions = {
        length: {
            'm': 1,
            'cm': 0.01,
            'mm': 0.001,
            'in': 0.0254,
            'px': 0.0254 / 96,
            'pt': 0.0254 / 72,
            'pc': 0.0254 / 72 * 12
        },
        duration: {
            's': 1,
            'ms': 0.001
        },
        angle: {
            'rad': 1 / (2 * Math.PI),
            'deg': 1 / 360,
            'grad': 1 / 400,
            'turn': 1
        }
    };

    tree.Unit = function (numerator, denominator, backupUnit) {
        this.numerator = numerator ? numerator.slice(0).sort() : [];
        this.denominator = denominator ? denominator.slice(0).sort() : [];
        this.backupUnit = backupUnit;
    };

    tree.Unit.prototype = {
        type: "Unit",
        clone: function () {
            return new tree.Unit(this.numerator.slice(0), this.denominator.slice(0), this.backupUnit);
        },
        genCSS: function (env, output) {
            if (this.numerator.length >= 1) {
                output.add(this.numerator[0]);
            } else if (this.denominator.length >= 1) {
                output.add(this.denominator[0]);
            } else if ((!env || !env.strictUnits) && this.backupUnit) {
                output.add(this.backupUnit);
            }
        },
        toCSS: tree.toCSS,

        toString: function () {
            var i, returnStr = this.numerator.join("*");
            for (i = 0; i < this.denominator.length; i++) {
                returnStr += "/" + this.denominator[i];
            }
            return returnStr;
        },

        compare: function (other) {
            return this.is(other.toString()) ? 0 : -1;
        },

        is: function (unitString) {
            return this.toString() === unitString;
        },

        isLength: function () {
            return Boolean(this.toCSS().match(/px|em|%|in|cm|mm|pc|pt|ex/));
        },

        isEmpty: function () {
            return this.numerator.length === 0 && this.denominator.length === 0;
        },

        isSingular: function () {
            return this.numerator.length <= 1 && this.denominator.length === 0;
        },

        map: function (callback) {
            var i;

            for (i = 0; i < this.numerator.length; i++) {
                this.numerator[i] = callback(this.numerator[i], false);
            }

            for (i = 0; i < this.denominator.length; i++) {
                this.denominator[i] = callback(this.denominator[i], true);
            }
        },

        usedUnits: function () {
            var group, result = {}, mapUnit;

            mapUnit = function (atomicUnit) {
                /*jshint loopfunc:true */
                if (group.hasOwnProperty(atomicUnit) && !result[groupName]) {
                    result[groupName] = atomicUnit;
                }

                return atomicUnit;
            };

            for (var groupName in tree.UnitConversions) {
                if (tree.UnitConversions.hasOwnProperty(groupName)) {
                    group = tree.UnitConversions[groupName];

                    this.map(mapUnit);
                }
            }

            return result;
        },

        cancel: function () {
            var counter = {}, atomicUnit, i, backup;

            for (i = 0; i < this.numerator.length; i++) {
                atomicUnit = this.numerator[i];
                if (!backup) {
                    backup = atomicUnit;
                }
                counter[atomicUnit] = (counter[atomicUnit] || 0) + 1;
            }

            for (i = 0; i < this.denominator.length; i++) {
                atomicUnit = this.denominator[i];
                if (!backup) {
                    backup = atomicUnit;
                }
                counter[atomicUnit] = (counter[atomicUnit] || 0) - 1;
            }

            this.numerator = [];
            this.denominator = [];

            for (atomicUnit in counter) {
                if (counter.hasOwnProperty(atomicUnit)) {
                    var count = counter[atomicUnit];

                    if (count > 0) {
                        for (i = 0; i < count; i++) {
                            this.numerator.push(atomicUnit);
                        }
                    } else if (count < 0) {
                        for (i = 0; i < -count; i++) {
                            this.denominator.push(atomicUnit);
                        }
                    }
                }
            }

            if (this.numerator.length === 0 && this.denominator.length === 0 && backup) {
                this.backupUnit = backup;
            }

            this.numerator.sort();
            this.denominator.sort();
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Directive = function (name, value, rules, index, currentFileInfo, debugInfo) {
        this.name = name;
        this.value = value;
        if (rules) {
            this.rules = rules;
            this.rules.allowImports = true;
        }
        this.index = index;
        this.currentFileInfo = currentFileInfo;
        this.debugInfo = debugInfo;
    };

    tree.Directive.prototype = {
        type: "Directive",
        accept: function (visitor) {
            var value = this.value, rules = this.rules;
            if (rules) {
                rules = visitor.visit(rules);
            }
            if (value) {
                value = visitor.visit(value);
            }
        },
        isRulesetLike: function () {
            return !this.isCharset();
        },
        isCharset: function () {
            return "@charset" === this.name;
        },
        genCSS: function (env, output) {
            var value = this.value, rules = this.rules;
            output.add(this.name, this.currentFileInfo, this.index);
            if (value) {
                output.add(' ');
                value.genCSS(env, output);
            }
            if (rules) {
                tree.outputRuleset(env, output, [rules]);
            } else {
                output.add(';');
            }
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            var value = this.value, rules = this.rules;
            if (value) {
                value = value.eval(env);
            }
            if (rules) {
                rules = rules.eval(env);
                rules.root = true;
            }
            return new (tree.Directive)(this.name, value, rules,
                this.index, this.currentFileInfo, this.debugInfo);
        },
        variable: function (name) {
            if (this.rules) return tree.Ruleset.prototype.variable.call(this.rules, name);
        },
        find: function () {
            if (this.rules) return tree.Ruleset.prototype.find.apply(this.rules, arguments);
        },
        rulesets: function () {
            if (this.rules) return tree.Ruleset.prototype.rulesets.apply(this.rules);
        },
        markReferenced: function () {
            var i, rules;
            this.isReferenced = true;
            if (this.rules) {
                rules = this.rules.rules;
                for (i = 0; i < rules.length; i++) {
                    if (rules[i].markReferenced) {
                        rules[i].markReferenced();
                    }
                }
            }
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Element = function (combinator, value, index, currentFileInfo) {
        this.combinator = combinator instanceof tree.Combinator ?
            combinator : new (tree.Combinator)(combinator);

        if (typeof(value) === 'string') {
            this.value = value.trim();
        } else if (value) {
            this.value = value;
        } else {
            this.value = "";
        }
        this.index = index;
        this.currentFileInfo = currentFileInfo;
    };
    tree.Element.prototype = {
        type: "Element",
        accept: function (visitor) {
            var value = this.value;
            this.combinator = visitor.visit(this.combinator);
            if (typeof value === "object") {
                this.value = visitor.visit(value);
            }
        },
        eval: function (env) {
            return new (tree.Element)(this.combinator,
                this.value.eval ? this.value.eval(env) : this.value,
                this.index,
                this.currentFileInfo);
        },
        genCSS: function (env, output) {
            output.add(this.toCSS(env), this.currentFileInfo, this.index);
        },
        toCSS: function (env) {
            var value = (this.value.toCSS ? this.value.toCSS(env) : this.value);
            if (value === '' && this.combinator.value.charAt(0) === '&') {
                return '';
            } else {
                return this.combinator.toCSS(env || {}) + value;
            }
        }
    };

    tree.Attribute = function (key, op, value) {
        this.key = key;
        this.op = op;
        this.value = value;
    };
    tree.Attribute.prototype = {
        type: "Attribute",
        eval: function (env) {
            return new (tree.Attribute)(this.key.eval ? this.key.eval(env) : this.key,
                this.op, (this.value && this.value.eval) ? this.value.eval(env) : this.value);
        },
        genCSS: function (env, output) {
            output.add(this.toCSS(env));
        },
        toCSS: function (env) {
            var value = this.key.toCSS ? this.key.toCSS(env) : this.key;

            if (this.op) {
                value += this.op;
                value += (this.value.toCSS ? this.value.toCSS(env) : this.value);
            }

            return '[' + value + ']';
        }
    };

    tree.Combinator = function (value) {
        if (value === ' ') {
            this.value = ' ';
        } else {
            this.value = value ? value.trim() : "";
        }
    };
    tree.Combinator.prototype = {
        type: "Combinator",
        _noSpaceCombinators: {
            '': true,
            ' ': true,
            '|': true
        },
        genCSS: function (env, output) {
            var spaceOrEmpty = (env.compress || this._noSpaceCombinators[this.value]) ? '' : ' ';
            output.add(spaceOrEmpty + this.value + spaceOrEmpty);
        },
        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {

    tree.Expression = function (value) {
        this.value = value;
    };
    tree.Expression.prototype = {
        type: "Expression",
        accept: function (visitor) {
            if (this.value) {
                this.value = visitor.visitArray(this.value);
            }
        },
        eval: function (env) {
            var returnValue,
                inParenthesis = this.parens && !this.parensInOp,
                doubleParen = false;
            if (inParenthesis) {
                env.inParenthesis();
            }
            if (this.value.length > 1) {
                returnValue = new (tree.Expression)(this.value.map(function (e) {
                    return e.eval(env);
                }));
            } else if (this.value.length === 1) {
                if (this.value[0].parens && !this.value[0].parensInOp) {
                    doubleParen = true;
                }
                returnValue = this.value[0].eval(env);
            } else {
                returnValue = this;
            }
            if (inParenthesis) {
                env.outOfParenthesis();
            }
            if (this.parens && this.parensInOp && !(env.isMathOn()) && !doubleParen) {
                returnValue = new (tree.Paren)(returnValue);
            }
            return returnValue;
        },
        genCSS: function (env, output) {
            for (var i = 0; i < this.value.length; i++) {
                this.value[i].genCSS(env, output);
                if (i + 1 < this.value.length) {
                    output.add(" ");
                }
            }
        },
        toCSS: tree.toCSS,
        throwAwayComments: function () {
            this.value = this.value.filter(function (v) {
                return !(v instanceof tree.Comment);
            });
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Extend = function Extend(selector, option, index) {
        this.selector = selector;
        this.option = option;
        this.index = index;
        this.object_id = tree.Extend.next_id++;
        this.parent_ids = [this.object_id];

        switch (option) {
            case "all":
                this.allowBefore = true;
                this.allowAfter = true;
                break;
            default:
                this.allowBefore = false;
                this.allowAfter = false;
                break;
        }
    };
    tree.Extend.next_id = 0;

    tree.Extend.prototype = {
        type: "Extend",
        accept: function (visitor) {
            this.selector = visitor.visit(this.selector);
        },
        eval: function (env) {
            return new (tree.Extend)(this.selector.eval(env), this.option, this.index);
        },
        clone: function (env) {
            return new (tree.Extend)(this.selector, this.option, this.index);
        },
        findSelfSelectors: function (selectors) {
            var selfElements = [],
                i,
                selectorElements;

            for (i = 0; i < selectors.length; i++) {
                selectorElements = selectors[i].elements;
                // duplicate the logic in genCSS function inside the selector node.
                // future TODO - move both logics into the selector joiner visitor
                if (i > 0 && selectorElements.length && selectorElements[0].combinator.value === "") {
                    selectorElements[0].combinator.value = ' ';
                }
                selfElements = selfElements.concat(selectors[i].elements);
            }

            this.selfSelectors = [{elements: selfElements}];
        }
    };

})(require('../tree'));

(function (tree) {
//
// CSS @import node
//
// The general strategy here is that we don't want to wait
// for the parsing to be completed, before we start importing
// the file. That's because in the context of a browser,
// most of the time will be spent waiting for the server to respond.
//
// On creation, we push the import path to our import queue, though
// `import,push`, we also pass it a callback, which it'll call once
// the file has been fetched, and parsed.
//
    tree.Import = function (path, features, options, index, currentFileInfo) {
        this.options = options;
        this.index = index;
        this.path = path;
        this.features = features;
        this.currentFileInfo = currentFileInfo;

        if (this.options.less !== undefined || this.options.inline) {
            this.css = !this.options.less || this.options.inline;
        } else {
            var pathValue = this.getPath();
            if (pathValue && /css([\?;].*)?$/.test(pathValue)) {
                this.css = true;
            }
        }
    };

//
// The actual import node doesn't return anything, when converted to CSS.
// The reason is that it's used at the evaluation stage, so that the rules
// it imports can be treated like any other rules.
//
// In `eval`, we make sure all Import nodes get evaluated, recursively, so
// we end up with a flat structure, which can easily be imported in the parent
// ruleset.
//
    tree.Import.prototype = {
        type: "Import",
        accept: function (visitor) {
            if (this.features) {
                this.features = visitor.visit(this.features);
            }
            this.path = visitor.visit(this.path);
            if (!this.options.inline && this.root) {
                this.root = visitor.visit(this.root);
            }
        },
        genCSS: function (env, output) {
            if (this.css) {
                output.add("@import ", this.currentFileInfo, this.index);
                this.path.genCSS(env, output);
                if (this.features) {
                    output.add(" ");
                    this.features.genCSS(env, output);
                }
                output.add(';');
            }
        },
        toCSS: tree.toCSS,
        getPath: function () {
            if (this.path instanceof tree.Quoted) {
                var path = this.path.value;
                return (this.css !== undefined || /(\.[a-z]*$)|([\?;].*)$/.test(path)) ? path : path + '.less';
            } else if (this.path instanceof tree.URL) {
                return this.path.value.value;
            }
            return null;
        },
        evalForImport: function (env) {
            return new (tree.Import)(this.path.eval(env), this.features, this.options, this.index, this.currentFileInfo);
        },
        evalPath: function (env) {
            var path = this.path.eval(env);
            var rootpath = this.currentFileInfo && this.currentFileInfo.rootpath;

            if (!(path instanceof tree.URL)) {
                if (rootpath) {
                    var pathValue = path.value;
                    // Add the base path if the import is relative
                    if (pathValue && env.isPathRelative(pathValue)) {
                        path.value = rootpath + pathValue;
                    }
                }
                path.value = env.normalizePath(path.value);
            }

            return path;
        },
        eval: function (env) {
            var ruleset, features = this.features && this.features.eval(env);

            if (this.skip) {
                if (typeof this.skip === "function") {
                    this.skip = this.skip();
                }
                if (this.skip) {
                    return [];
                }
            }

            if (this.options.inline) {
                //todo needs to reference css file not import
                var contents = new (tree.Anonymous)(this.root, 0, {filename: this.importedFilename}, true, true);
                return this.features ? new (tree.Media)([contents], this.features.value) : [contents];
            } else if (this.css) {
                var newImport = new (tree.Import)(this.evalPath(env), features, this.options, this.index);
                if (!newImport.css && this.error) {
                    throw this.error;
                }
                return newImport;
            } else {
                ruleset = new (tree.Ruleset)(null, this.root.rules.slice(0));

                ruleset.evalImports(env);

                return this.features ? new (tree.Media)(ruleset.rules, this.features.value) : ruleset.rules;
            }
        }
    };

})(require('../tree'));

(function (tree) {

    tree.JavaScript = function (string, index, escaped) {
        this.escaped = escaped;
        this.expression = string;
        this.index = index;
    };
    tree.JavaScript.prototype = {
        type: "JavaScript",
        eval: function (env) {
            var result,
                that = this,
                context = {};

            var expression = this.expression.replace(/@\{([\w-]+)\}/g, function (_, name) {
                return tree.jsify(new (tree.Variable)('@' + name, that.index).eval(env));
            });

            try {
                expression = new (Function)('return (' + expression + ')');
            } catch (e) {
                throw {
                    message: "JavaScript evaluation error: " + e.message + " from `" + expression + "`",
                    index: this.index
                };
            }

            var variables = env.frames[0].variables();
            for (var k in variables) {
                if (variables.hasOwnProperty(k)) {
                    /*jshint loopfunc:true */
                    context[k.slice(1)] = {
                        value: variables[k].value,
                        toJS: function () {
                            return this.value.eval(env).toCSS();
                        }
                    };
                }
            }

            try {
                result = expression.call(context);
            } catch (e) {
                throw {
                    message: "JavaScript evaluation error: '" + e.name + ': ' + e.message.replace(/["]/g, "'") + "'",
                    index: this.index
                };
            }
            if (typeof(result) === 'number') {
                return new (tree.Dimension)(result);
            } else if (typeof(result) === 'string') {
                return new (tree.Quoted)('"' + result + '"', result, this.escaped, this.index);
            } else if (Array.isArray(result)) {
                return new (tree.Anonymous)(result.join(', '));
            } else {
                return new (tree.Anonymous)(result);
            }
        }
    };

})(require('../tree'));


(function (tree) {

    tree.Keyword = function (value) {
        this.value = value;
    };
    tree.Keyword.prototype = {
        type: "Keyword",
        eval: function () {
            return this;
        },
        genCSS: function (env, output) {
            if (this.value === '%') {
                throw {type: "Syntax", message: "Invalid % without number"};
            }
            output.add(this.value);
        },
        toCSS: tree.toCSS,
        compare: function (other) {
            if (other instanceof tree.Keyword) {
                return other.value === this.value ? 0 : 1;
            } else {
                return -1;
            }
        }
    };

    tree.True = new (tree.Keyword)('true');
    tree.False = new (tree.Keyword)('false');

})(require('../tree'));

(function (tree) {

    tree.Media = function (value, features, index, currentFileInfo) {
        this.index = index;
        this.currentFileInfo = currentFileInfo;

        var selectors = this.emptySelectors();

        this.features = new (tree.Value)(features);
        this.rules = [new (tree.Ruleset)(selectors, value)];
        this.rules[0].allowImports = true;
    };
    tree.Media.prototype = {
        type: "Media",
        accept: function (visitor) {
            if (this.features) {
                this.features = visitor.visit(this.features);
            }
            if (this.rules) {
                this.rules = visitor.visitArray(this.rules);
            }
        },
        genCSS: function (env, output) {
            output.add('@media ', this.currentFileInfo, this.index);
            this.features.genCSS(env, output);
            tree.outputRuleset(env, output, this.rules);
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            if (!env.mediaBlocks) {
                env.mediaBlocks = [];
                env.mediaPath = [];
            }

            var media = new (tree.Media)(null, [], this.index, this.currentFileInfo);
            if (this.debugInfo) {
                this.rules[0].debugInfo = this.debugInfo;
                media.debugInfo = this.debugInfo;
            }
            var strictMathBypass = false;
            if (!env.strictMath) {
                strictMathBypass = true;
                env.strictMath = true;
            }
            try {
                media.features = this.features.eval(env);
            }
            finally {
                if (strictMathBypass) {
                    env.strictMath = false;
                }
            }

            env.mediaPath.push(media);
            env.mediaBlocks.push(media);

            env.frames.unshift(this.rules[0]);
            media.rules = [this.rules[0].eval(env)];
            env.frames.shift();

            env.mediaPath.pop();

            return env.mediaPath.length === 0 ? media.evalTop(env) :
                media.evalNested(env);
        },
        variable: function (name) {
            return tree.Ruleset.prototype.variable.call(this.rules[0], name);
        },
        find: function () {
            return tree.Ruleset.prototype.find.apply(this.rules[0], arguments);
        },
        rulesets: function () {
            return tree.Ruleset.prototype.rulesets.apply(this.rules[0]);
        },
        emptySelectors: function () {
            var el = new (tree.Element)('', '&', this.index, this.currentFileInfo),
                sels = [new (tree.Selector)([el], null, null, this.index, this.currentFileInfo)];
            sels[0].mediaEmpty = true;
            return sels;
        },
        markReferenced: function () {
            var i, rules = this.rules[0].rules;
            this.rules[0].markReferenced();
            this.isReferenced = true;
            for (i = 0; i < rules.length; i++) {
                if (rules[i].markReferenced) {
                    rules[i].markReferenced();
                }
            }
        },

        evalTop: function (env) {
            var result = this;

            // Render all dependent Media blocks.
            if (env.mediaBlocks.length > 1) {
                var selectors = this.emptySelectors();
                result = new (tree.Ruleset)(selectors, env.mediaBlocks);
                result.multiMedia = true;
            }

            delete env.mediaBlocks;
            delete env.mediaPath;

            return result;
        },
        evalNested: function (env) {
            var i, value,
                path = env.mediaPath.concat([this]);

            // Extract the media-query conditions separated with `,` (OR).
            for (i = 0; i < path.length; i++) {
                value = path[i].features instanceof tree.Value ?
                    path[i].features.value : path[i].features;
                path[i] = Array.isArray(value) ? value : [value];
            }

            // Trace all permutations to generate the resulting media-query.
            //
            // (a, b and c) with nested (d, e) ->
            //    a and d
            //    a and e
            //    b and c and d
            //    b and c and e
            this.features = new (tree.Value)(this.permute(path).map(function (path) {
                path = path.map(function (fragment) {
                    return fragment.toCSS ? fragment : new (tree.Anonymous)(fragment);
                });

                for (i = path.length - 1; i > 0; i--) {
                    path.splice(i, 0, new (tree.Anonymous)("and"));
                }

                return new (tree.Expression)(path);
            }));

            // Fake a tree-node that doesn't output anything.
            return new (tree.Ruleset)([], []);
        },
        permute: function (arr) {
            if (arr.length === 0) {
                return [];
            } else if (arr.length === 1) {
                return arr[0];
            } else {
                var result = [];
                var rest = this.permute(arr.slice(1));
                for (var i = 0; i < rest.length; i++) {
                    for (var j = 0; j < arr[0].length; j++) {
                        result.push([arr[0][j]].concat(rest[i]));
                    }
                }
                return result;
            }
        },
        bubbleSelectors: function (selectors) {
            if (!selectors)
                return;
            this.rules = [new (tree.Ruleset)(selectors.slice(0), [this.rules[0]])];
        }
    };

})(require('../tree'));

(function (tree) {

    tree.mixin = {};
    tree.mixin.Call = function (elements, args, index, currentFileInfo, important) {
        this.selector = new (tree.Selector)(elements);
        this.arguments = (args && args.length) ? args : null;
        this.index = index;
        this.currentFileInfo = currentFileInfo;
        this.important = important;
    };
    tree.mixin.Call.prototype = {
        type: "MixinCall",
        accept: function (visitor) {
            if (this.selector) {
                this.selector = visitor.visit(this.selector);
            }
            if (this.arguments) {
                this.arguments = visitor.visitArray(this.arguments);
            }
        },
        eval: function (env) {
            var mixins, mixin, args, rules = [], match = false, i, m, f, isRecursive, isOneFound, rule,
                candidates = [], candidate, conditionResult = [], defaultFunc = tree.defaultFunc,
                defaultResult, defNone = 0, defTrue = 1, defFalse = 2, count, originalRuleset;

            args = this.arguments && this.arguments.map(function (a) {
                return {name: a.name, value: a.value.eval(env)};
            });

            for (i = 0; i < env.frames.length; i++) {
                if ((mixins = env.frames[i].find(this.selector)).length > 0) {
                    isOneFound = true;

                    // To make `default()` function independent of definition order we have two "subpasses" here.
                    // At first we evaluate each guard *twice* (with `default() == true` and `default() == false`),
                    // and build candidate list with corresponding flags. Then, when we know all possible matches,
                    // we make a final decision.

                    for (m = 0; m < mixins.length; m++) {
                        mixin = mixins[m];
                        isRecursive = false;
                        for (f = 0; f < env.frames.length; f++) {
                            if ((!(mixin instanceof tree.mixin.Definition)) && mixin === (env.frames[f].originalRuleset || env.frames[f])) {
                                isRecursive = true;
                                break;
                            }
                        }
                        if (isRecursive) {
                            continue;
                        }

                        if (mixin.matchArgs(args, env)) {
                            candidate = {mixin: mixin, group: defNone};

                            if (mixin.matchCondition) {
                                for (f = 0; f < 2; f++) {
                                    defaultFunc.value(f);
                                    conditionResult[f] = mixin.matchCondition(args, env);
                                }
                                if (conditionResult[0] || conditionResult[1]) {
                                    if (conditionResult[0] != conditionResult[1]) {
                                        candidate.group = conditionResult[1] ?
                                            defTrue : defFalse;
                                    }

                                    candidates.push(candidate);
                                }
                            }
                            else {
                                candidates.push(candidate);
                            }

                            match = true;
                        }
                    }

                    defaultFunc.reset();

                    count = [0, 0, 0];
                    for (m = 0; m < candidates.length; m++) {
                        count[candidates[m].group]++;
                    }

                    if (count[defNone] > 0) {
                        defaultResult = defFalse;
                    } else {
                        defaultResult = defTrue;
                        if ((count[defTrue] + count[defFalse]) > 1) {
                            throw {
                                type: 'Runtime',
                                message: 'Ambiguous use of `default()` found when matching for `'
                                + this.format(args) + '`',
                                index: this.index, filename: this.currentFileInfo.filename
                            };
                        }
                    }

                    for (m = 0; m < candidates.length; m++) {
                        candidate = candidates[m].group;
                        if ((candidate === defNone) || (candidate === defaultResult)) {
                            try {
                                mixin = candidates[m].mixin;
                                if (!(mixin instanceof tree.mixin.Definition)) {
                                    originalRuleset = mixin.originalRuleset || mixin;
                                    mixin = new tree.mixin.Definition("", [], mixin.rules, null, false);
                                    mixin.originalRuleset = originalRuleset;
                                }
                                Array.prototype.push.apply(
                                    rules, mixin.evalCall(env, args, this.important).rules);
                            } catch (e) {
                                throw {
                                    message: e.message,
                                    index: this.index,
                                    filename: this.currentFileInfo.filename,
                                    stack: e.stack
                                };
                            }
                        }
                    }

                    if (match) {
                        if (!this.currentFileInfo || !this.currentFileInfo.reference) {
                            for (i = 0; i < rules.length; i++) {
                                rule = rules[i];
                                if (rule.markReferenced) {
                                    rule.markReferenced();
                                }
                            }
                        }
                        return rules;
                    }
                }
            }
            if (isOneFound) {
                throw {
                    type: 'Runtime',
                    message: 'No matching definition was found for `' + this.format(args) + '`',
                    index: this.index, filename: this.currentFileInfo.filename
                };
            } else {
                throw {
                    type: 'Name',
                    message: this.selector.toCSS().trim() + " is undefined",
                    index: this.index, filename: this.currentFileInfo.filename
                };
            }
        },
        format: function (args) {
            return this.selector.toCSS().trim() + '(' +
                (args ? args.map(function (a) {
                    var argValue = "";
                    if (a.name) {
                        argValue += a.name + ":";
                    }
                    if (a.value.toCSS) {
                        argValue += a.value.toCSS();
                    } else {
                        argValue += "???";
                    }
                    return argValue;
                }).join(', ') : "") + ")";
        }
    };

    tree.mixin.Definition = function (name, params, rules, condition, variadic, frames) {
        this.name = name;
        this.selectors = [new (tree.Selector)([new (tree.Element)(null, name, this.index, this.currentFileInfo)])];
        this.params = params;
        this.condition = condition;
        this.variadic = variadic;
        this.arity = params.length;
        this.rules = rules;
        this._lookups = {};
        this.required = params.reduce(function (count, p) {
            if (!p.name || (p.name && !p.value)) {
                return count + 1;
            }
            else {
                return count;
            }
        }, 0);
        this.parent = tree.Ruleset.prototype;
        this.frames = frames;
    };
    tree.mixin.Definition.prototype = {
        type: "MixinDefinition",
        accept: function (visitor) {
            if (this.params && this.params.length) {
                this.params = visitor.visitArray(this.params);
            }
            this.rules = visitor.visitArray(this.rules);
            if (this.condition) {
                this.condition = visitor.visit(this.condition);
            }
        },
        variable: function (name) {
            return this.parent.variable.call(this, name);
        },
        variables: function () {
            return this.parent.variables.call(this);
        },
        find: function () {
            return this.parent.find.apply(this, arguments);
        },
        rulesets: function () {
            return this.parent.rulesets.apply(this);
        },

        evalParams: function (env, mixinEnv, args, evaldArguments) {
            /*jshint boss:true */
            var frame = new (tree.Ruleset)(null, null),
                varargs, arg,
                params = this.params.slice(0),
                i, j, val, name, isNamedFound, argIndex, argsLength = 0;

            mixinEnv = new tree.evalEnv(mixinEnv, [frame].concat(mixinEnv.frames));

            if (args) {
                args = args.slice(0);
                argsLength = args.length;

                for (i = 0; i < argsLength; i++) {
                    arg = args[i];
                    if (name = (arg && arg.name)) {
                        isNamedFound = false;
                        for (j = 0; j < params.length; j++) {
                            if (!evaldArguments[j] && name === params[j].name) {
                                evaldArguments[j] = arg.value.eval(env);
                                frame.prependRule(new (tree.Rule)(name, arg.value.eval(env)));
                                isNamedFound = true;
                                break;
                            }
                        }
                        if (isNamedFound) {
                            args.splice(i, 1);
                            i--;
                            continue;
                        } else {
                            throw {
                                type: 'Runtime', message: "Named argument for " + this.name +
                                ' ' + args[i].name + ' not found'
                            };
                        }
                    }
                }
            }
            argIndex = 0;
            for (i = 0; i < params.length; i++) {
                if (evaldArguments[i]) {
                    continue;
                }

                arg = args && args[argIndex];

                if (name = params[i].name) {
                    if (params[i].variadic) {
                        varargs = [];
                        for (j = argIndex; j < argsLength; j++) {
                            varargs.push(args[j].value.eval(env));
                        }
                        frame.prependRule(new (tree.Rule)(name, new (tree.Expression)(varargs).eval(env)));
                    } else {
                        val = arg && arg.value;
                        if (val) {
                            val = val.eval(env);
                        } else if (params[i].value) {
                            val = params[i].value.eval(mixinEnv);
                            frame.resetCache();
                        } else {
                            throw {
                                type: 'Runtime', message: "wrong number of arguments for " + this.name +
                                ' (' + argsLength + ' for ' + this.arity + ')'
                            };
                        }

                        frame.prependRule(new (tree.Rule)(name, val));
                        evaldArguments[i] = val;
                    }
                }

                if (params[i].variadic && args) {
                    for (j = argIndex; j < argsLength; j++) {
                        evaldArguments[j] = args[j].value.eval(env);
                    }
                }
                argIndex++;
            }

            return frame;
        },
        eval: function (env) {
            return new tree.mixin.Definition(this.name, this.params, this.rules, this.condition, this.variadic, this.frames || env.frames.slice(0));
        },
        evalCall: function (env, args, important) {
            var _arguments = [],
                mixinFrames = this.frames ? this.frames.concat(env.frames) : env.frames,
                frame = this.evalParams(env, new (tree.evalEnv)(env, mixinFrames), args, _arguments),
                rules, ruleset;

            frame.prependRule(new (tree.Rule)('@arguments', new (tree.Expression)(_arguments).eval(env)));

            rules = this.rules.slice(0);

            ruleset = new (tree.Ruleset)(null, rules);
            ruleset.originalRuleset = this;
            ruleset = ruleset.eval(new (tree.evalEnv)(env, [this, frame].concat(mixinFrames)));
            if (important) {
                ruleset = this.parent.makeImportant.apply(ruleset);
            }
            return ruleset;
        },
        matchCondition: function (args, env) {
            if (this.condition && !this.condition.eval(
                    new (tree.evalEnv)(env,
                        [this.evalParams(env, new (tree.evalEnv)(env, this.frames ? this.frames.concat(env.frames) : env.frames), args, [])] // the parameter variables
                            .concat(this.frames) // the parent namespace/mixin frames
                            .concat(env.frames)))) { // the current environment frames
                return false;
            }
            return true;
        },
        matchArgs: function (args, env) {
            var argsLength = (args && args.length) || 0, len;

            if (!this.variadic) {
                if (argsLength < this.required) {
                    return false;
                }
                if (argsLength > this.params.length) {
                    return false;
                }
            } else {
                if (argsLength < (this.required - 1)) {
                    return false;
                }
            }

            len = Math.min(argsLength, this.arity);

            for (var i = 0; i < len; i++) {
                if (!this.params[i].name && !this.params[i].variadic) {
                    if (args[i].value.eval(env).toCSS() != this.params[i].value.eval(env).toCSS()) {
                        return false;
                    }
                }
            }
            return true;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Negative = function (node) {
        this.value = node;
    };
    tree.Negative.prototype = {
        type: "Negative",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        genCSS: function (env, output) {
            output.add('-');
            this.value.genCSS(env, output);
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            if (env.isMathOn()) {
                return (new (tree.Operation)('*', [new (tree.Dimension)(-1), this.value])).eval(env);
            }
            return new (tree.Negative)(this.value.eval(env));
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Operation = function (op, operands, isSpaced) {
        this.op = op.trim();
        this.operands = operands;
        this.isSpaced = isSpaced;
    };
    tree.Operation.prototype = {
        type: "Operation",
        accept: function (visitor) {
            this.operands = visitor.visit(this.operands);
        },
        eval: function (env) {
            var a = this.operands[0].eval(env),
                b = this.operands[1].eval(env);

            if (env.isMathOn()) {
                if (a instanceof tree.Dimension && b instanceof tree.Color) {
                    a = a.toColor();
                }
                if (b instanceof tree.Dimension && a instanceof tree.Color) {
                    b = b.toColor();
                }
                if (!a.operate) {
                    throw {
                        type: "Operation",
                        message: "Operation on an invalid type"
                    };
                }

                return a.operate(env, this.op, b);
            } else {
                return new (tree.Operation)(this.op, [a, b], this.isSpaced);
            }
        },
        genCSS: function (env, output) {
            this.operands[0].genCSS(env, output);
            if (this.isSpaced) {
                output.add(" ");
            }
            output.add(this.op);
            if (this.isSpaced) {
                output.add(" ");
            }
            this.operands[1].genCSS(env, output);
        },
        toCSS: tree.toCSS
    };

    tree.operate = function (env, op, a, b) {
        switch (op) {
            case '+':
                return a + b;
            case '-':
                return a - b;
            case '*':
                return a * b;
            case '/':
                return a / b;
        }
    };

})(require('../tree'));


(function (tree) {

    tree.Paren = function (node) {
        this.value = node;
    };
    tree.Paren.prototype = {
        type: "Paren",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        genCSS: function (env, output) {
            output.add('(');
            this.value.genCSS(env, output);
            output.add(')');
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            return new (tree.Paren)(this.value.eval(env));
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Quoted = function (str, content, escaped, index, currentFileInfo) {
        this.escaped = escaped;
        this.value = content || '';
        this.quote = str.charAt(0);
        this.index = index;
        this.currentFileInfo = currentFileInfo;
    };
    tree.Quoted.prototype = {
        type: "Quoted",
        genCSS: function (env, output) {
            if (!this.escaped) {
                output.add(this.quote, this.currentFileInfo, this.index);
            }
            output.add(this.value);
            if (!this.escaped) {
                output.add(this.quote);
            }
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            var that = this;
            var value = this.value.replace(/`([^`]+)`/g, function (_, exp) {
                return new (tree.JavaScript)(exp, that.index, true).eval(env).value;
            }).replace(/@\{([\w-]+)\}/g, function (_, name) {
                var v = new (tree.Variable)('@' + name, that.index, that.currentFileInfo).eval(env, true);
                return (v instanceof tree.Quoted) ? v.value : v.toCSS();
            });
            return new (tree.Quoted)(this.quote + value + this.quote, value, this.escaped, this.index, this.currentFileInfo);
        },
        compare: function (x) {
            if (!x.toCSS) {
                return -1;
            }

            var left, right;

            // when comparing quoted strings allow the quote to differ
            if (x.type === "Quoted" && !this.escaped && !x.escaped) {
                left = x.value;
                right = this.value;
            } else {
                left = this.toCSS();
                right = x.toCSS();
            }

            if (left === right) {
                return 0;
            }

            return left < right ? -1 : 1;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Rule = function (name, value, important, merge, index, currentFileInfo, inline, variable) {
        this.name = name;
        this.value = (value instanceof tree.Value || value instanceof tree.Ruleset) ? value : new (tree.Value)([value]);
        this.important = important ? ' ' + important.trim() : '';
        this.merge = merge;
        this.index = index;
        this.currentFileInfo = currentFileInfo;
        this.inline = inline || false;
        this.variable = (variable !== undefined) ? variable
            : (name.charAt && (name.charAt(0) === '@'));
    };

    tree.Rule.prototype = {
        type: "Rule",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        genCSS: function (env, output) {
            output.add(this.name + (env.compress ? ':' : ': '), this.currentFileInfo, this.index);
            try {
                this.value.genCSS(env, output);
            }
            catch (e) {
                e.index = this.index;
                e.filename = this.currentFileInfo.filename;
                throw e;
            }
            output.add(this.important + ((this.inline || (env.lastRule && env.compress)) ? "" : ";"), this.currentFileInfo, this.index);
        },
        toCSS: tree.toCSS,
        eval: function (env) {
            var strictMathBypass = false, name = this.name, variable = this.variable, evaldValue;
            if (typeof name !== "string") {
                // expand 'primitive' name directly to get
                // things faster (~10% for benchmark.less):
                name = (name.length === 1)
                && (name[0] instanceof tree.Keyword)
                    ? name[0].value : evalName(env, name);
                variable = false; // never treat expanded interpolation as new variable name
            }
            if (name === "font" && !env.strictMath) {
                strictMathBypass = true;
                env.strictMath = true;
            }
            try {
                evaldValue = this.value.eval(env);

                if (!this.variable && evaldValue.type === "DetachedRuleset") {
                    throw {
                        message: "Rulesets cannot be evaluated on a property.",
                        index: this.index, filename: this.currentFileInfo.filename
                    };
                }

                return new (tree.Rule)(name,
                    evaldValue,
                    this.important,
                    this.merge,
                    this.index, this.currentFileInfo, this.inline,
                    variable);
            }
            catch (e) {
                if (typeof e.index !== 'number') {
                    e.index = this.index;
                    e.filename = this.currentFileInfo.filename;
                }
                throw e;
            }
            finally {
                if (strictMathBypass) {
                    env.strictMath = false;
                }
            }
        },
        makeImportant: function () {
            return new (tree.Rule)(this.name,
                this.value,
                "!important",
                this.merge,
                this.index, this.currentFileInfo, this.inline);
        }
    };

    function evalName(env, name) {
        var value = "", i, n = name.length,
            output = {
                add: function (s) {
                    value += s;
                }
            };
        for (i = 0; i < n; i++) {
            name[i].eval(env).genCSS(env, output);
        }
        return value;
    }

})(require('../tree'));

(function (tree) {

    tree.RulesetCall = function (variable) {
        this.variable = variable;
    };
    tree.RulesetCall.prototype = {
        type: "RulesetCall",
        accept: function (visitor) {
        },
        eval: function (env) {
            var detachedRuleset = new (tree.Variable)(this.variable).eval(env);
            return detachedRuleset.callEval(env);
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Ruleset = function (selectors, rules, strictImports) {
        this.selectors = selectors;
        this.rules = rules;
        this._lookups = {};
        this.strictImports = strictImports;
    };
    tree.Ruleset.prototype = {
        type: "Ruleset",
        accept: function (visitor) {
            if (this.paths) {
                visitor.visitArray(this.paths, true);
            } else if (this.selectors) {
                this.selectors = visitor.visitArray(this.selectors);
            }
            if (this.rules && this.rules.length) {
                this.rules = visitor.visitArray(this.rules);
            }
        },
        eval: function (env) {
            var thisSelectors = this.selectors, selectors,
                selCnt, selector, i, defaultFunc = tree.defaultFunc, hasOnePassingSelector = false;

            if (thisSelectors && (selCnt = thisSelectors.length)) {
                selectors = [];
                defaultFunc.error({
                    type: "Syntax",
                    message: "it is currently only allowed in parametric mixin guards,"
                });
                for (i = 0; i < selCnt; i++) {
                    selector = thisSelectors[i].eval(env);
                    selectors.push(selector);
                    if (selector.evaldCondition) {
                        hasOnePassingSelector = true;
                    }
                }
                defaultFunc.reset();
            } else {
                hasOnePassingSelector = true;
            }

            var rules = this.rules ? this.rules.slice(0) : null,
                ruleset = new (tree.Ruleset)(selectors, rules, this.strictImports),
                rule, subRule;

            ruleset.originalRuleset = this;
            ruleset.root = this.root;
            ruleset.firstRoot = this.firstRoot;
            ruleset.allowImports = this.allowImports;

            if (this.debugInfo) {
                ruleset.debugInfo = this.debugInfo;
            }

            if (!hasOnePassingSelector) {
                rules.length = 0;
            }

            // push the current ruleset to the frames stack
            var envFrames = env.frames;
            envFrames.unshift(ruleset);

            // currrent selectors
            var envSelectors = env.selectors;
            if (!envSelectors) {
                env.selectors = envSelectors = [];
            }
            envSelectors.unshift(this.selectors);

            // Evaluate imports
            if (ruleset.root || ruleset.allowImports || !ruleset.strictImports) {
                ruleset.evalImports(env);
            }

            // Store the frames around mixin definitions,
            // so they can be evaluated like closures when the time comes.
            var rsRules = ruleset.rules, rsRuleCnt = rsRules ? rsRules.length : 0;
            for (i = 0; i < rsRuleCnt; i++) {
                if (rsRules[i] instanceof tree.mixin.Definition || rsRules[i] instanceof tree.DetachedRuleset) {
                    rsRules[i] = rsRules[i].eval(env);
                }
            }

            var mediaBlockCount = (env.mediaBlocks && env.mediaBlocks.length) || 0;

            // Evaluate mixin calls.
            for (i = 0; i < rsRuleCnt; i++) {
                if (rsRules[i] instanceof tree.mixin.Call) {
                    /*jshint loopfunc:true */
                    rules = rsRules[i].eval(env).filter(function (r) {
                        if ((r instanceof tree.Rule) && r.variable) {
                            // do not pollute the scope if the variable is
                            // already there. consider returning false here
                            // but we need a way to "return" variable from mixins
                            return !(ruleset.variable(r.name));
                        }
                        return true;
                    });
                    rsRules.splice.apply(rsRules, [i, 1].concat(rules));
                    rsRuleCnt += rules.length - 1;
                    i += rules.length - 1;
                    ruleset.resetCache();
                } else if (rsRules[i] instanceof tree.RulesetCall) {
                    /*jshint loopfunc:true */
                    rules = rsRules[i].eval(env).rules.filter(function (r) {
                        if ((r instanceof tree.Rule) && r.variable) {
                            // do not pollute the scope at all
                            return false;
                        }
                        return true;
                    });
                    rsRules.splice.apply(rsRules, [i, 1].concat(rules));
                    rsRuleCnt += rules.length - 1;
                    i += rules.length - 1;
                    ruleset.resetCache();
                }
            }

            // Evaluate everything else
            for (i = 0; i < rsRules.length; i++) {
                rule = rsRules[i];
                if (!(rule instanceof tree.mixin.Definition || rule instanceof tree.DetachedRuleset)) {
                    rsRules[i] = rule = rule.eval ? rule.eval(env) : rule;
                }
            }

            // Evaluate everything else
            for (i = 0; i < rsRules.length; i++) {
                rule = rsRules[i];
                // for rulesets, check if it is a css guard and can be removed
                if (rule instanceof tree.Ruleset && rule.selectors && rule.selectors.length === 1) {
                    // check if it can be folded in (e.g. & where)
                    if (rule.selectors[0].isJustParentSelector()) {
                        rsRules.splice(i--, 1);

                        for (var j = 0; j < rule.rules.length; j++) {
                            subRule = rule.rules[j];
                            if (!(subRule instanceof tree.Rule) || !subRule.variable) {
                                rsRules.splice(++i, 0, subRule);
                            }
                        }
                    }
                }
            }

            // Pop the stack
            envFrames.shift();
            envSelectors.shift();

            if (env.mediaBlocks) {
                for (i = mediaBlockCount; i < env.mediaBlocks.length; i++) {
                    env.mediaBlocks[i].bubbleSelectors(selectors);
                }
            }

            return ruleset;
        },
        evalImports: function (env) {
            var rules = this.rules, i, importRules;
            if (!rules) {
                return;
            }

            for (i = 0; i < rules.length; i++) {
                if (rules[i] instanceof tree.Import) {
                    importRules = rules[i].eval(env);
                    if (importRules && importRules.length) {
                        rules.splice.apply(rules, [i, 1].concat(importRules));
                        i += importRules.length - 1;
                    } else {
                        rules.splice(i, 1, importRules);
                    }
                    this.resetCache();
                }
            }
        },
        makeImportant: function () {
            return new tree.Ruleset(this.selectors, this.rules.map(function (r) {
                if (r.makeImportant) {
                    return r.makeImportant();
                } else {
                    return r;
                }
            }), this.strictImports);
        },
        matchArgs: function (args) {
            return !args || args.length === 0;
        },
        // lets you call a css selector with a guard
        matchCondition: function (args, env) {
            var lastSelector = this.selectors[this.selectors.length - 1];
            if (!lastSelector.evaldCondition) {
                return false;
            }
            if (lastSelector.condition && !lastSelector.condition.eval(
                    new (tree.evalEnv)(env,
                        env.frames))) {
                return false;
            }
            return true;
        },
        resetCache: function () {
            this._rulesets = null;
            this._variables = null;
            this._lookups = {};
        },
        variables: function () {
            if (!this._variables) {
                this._variables = !this.rules ? {} : this.rules.reduce(function (hash, r) {
                    if (r instanceof tree.Rule && r.variable === true) {
                        hash[r.name] = r;
                    }
                    return hash;
                }, {});
            }
            return this._variables;
        },
        variable: function (name) {
            return this.variables()[name];
        },
        rulesets: function () {
            if (!this.rules) {
                return null;
            }

            var _Ruleset = tree.Ruleset, _MixinDefinition = tree.mixin.Definition,
                filtRules = [], rules = this.rules, cnt = rules.length,
                i, rule;

            for (i = 0; i < cnt; i++) {
                rule = rules[i];
                if ((rule instanceof _Ruleset) || (rule instanceof _MixinDefinition)) {
                    filtRules.push(rule);
                }
            }

            return filtRules;
        },
        prependRule: function (rule) {
            var rules = this.rules;
            if (rules) {
                rules.unshift(rule);
            } else {
                this.rules = [rule];
            }
        },
        find: function (selector, self) {
            self = self || this;
            var rules = [], match,
                key = selector.toCSS();

            if (key in this._lookups) {
                return this._lookups[key];
            }

            this.rulesets().forEach(function (rule) {
                if (rule !== self) {
                    for (var j = 0; j < rule.selectors.length; j++) {
                        match = selector.match(rule.selectors[j]);
                        if (match) {
                            if (selector.elements.length > match) {
                                Array.prototype.push.apply(rules, rule.find(
                                    new (tree.Selector)(selector.elements.slice(match)), self));
                            } else {
                                rules.push(rule);
                            }
                            break;
                        }
                    }
                }
            });
            this._lookups[key] = rules;
            return rules;
        },
        genCSS: function (env, output) {
            var i, j,
                charsetRuleNodes = [],
                ruleNodes = [],
                rulesetNodes = [],
                rulesetNodeCnt,
                debugInfo,     // Line number debugging
                rule,
                path;

            env.tabLevel = (env.tabLevel || 0);

            if (!this.root) {
                env.tabLevel++;
            }

            var tabRuleStr = env.compress ? '' : Array(env.tabLevel + 1).join("  "),
                tabSetStr = env.compress ? '' : Array(env.tabLevel).join("  "),
                sep;

            function isRulesetLikeNode(rule, root) {
                // if it has nested rules, then it should be treated like a ruleset
                if (rule.rules)
                    return true;

                // medias and comments do not have nested rules, but should be treated like rulesets anyway
                if ((rule instanceof tree.Media) || (root && rule instanceof tree.Comment))
                    return true;

                // some directives and anonumoust nodes are ruleset like, others are not
                if ((rule instanceof tree.Directive) || (rule instanceof tree.Anonymous)) {
                    return rule.isRulesetLike();
                }

                //anything else is assumed to be a rule
                return false;
            }

            for (i = 0; i < this.rules.length; i++) {
                rule = this.rules[i];
                if (isRulesetLikeNode(rule, this.root)) {
                    rulesetNodes.push(rule);
                } else {
                    //charsets should float on top of everything
                    if (rule.isCharset && rule.isCharset()) {
                        charsetRuleNodes.push(rule);
                    } else {
                        ruleNodes.push(rule);
                    }
                }
            }
            ruleNodes = charsetRuleNodes.concat(ruleNodes);

            // If this is the root node, we don't render
            // a selector, or {}.
            if (!this.root) {
                debugInfo = tree.debugInfo(env, this, tabSetStr);

                if (debugInfo) {
                    output.add(debugInfo);
                    output.add(tabSetStr);
                }

                var paths = this.paths, pathCnt = paths.length,
                    pathSubCnt;

                sep = env.compress ? ',' : (',\n' + tabSetStr);

                for (i = 0; i < pathCnt; i++) {
                    path = paths[i];
                    if (!(pathSubCnt = path.length)) {
                        continue;
                    }
                    if (i > 0) {
                        output.add(sep);
                    }

                    env.firstSelector = true;
                    path[0].genCSS(env, output);

                    env.firstSelector = false;
                    for (j = 1; j < pathSubCnt; j++) {
                        path[j].genCSS(env, output);
                    }
                }

                output.add((env.compress ? '{' : ' {\n') + tabRuleStr);
            }

            // Compile rules and rulesets
            for (i = 0; i < ruleNodes.length; i++) {
                rule = ruleNodes[i];

                // @page{ directive ends up with root elements inside it, a mix of rules and rulesets
                // In this instance we do not know whether it is the last property
                if (i + 1 === ruleNodes.length && (!this.root || rulesetNodes.length === 0 || this.firstRoot)) {
                    env.lastRule = true;
                }

                if (rule.genCSS) {
                    rule.genCSS(env, output);
                } else if (rule.value) {
                    output.add(rule.value.toString());
                }

                if (!env.lastRule) {
                    output.add(env.compress ? '' : ('\n' + tabRuleStr));
                } else {
                    env.lastRule = false;
                }
            }

            if (!this.root) {
                output.add((env.compress ? '}' : '\n' + tabSetStr + '}'));
                env.tabLevel--;
            }

            sep = (env.compress ? "" : "\n") + (this.root ? tabRuleStr : tabSetStr);
            rulesetNodeCnt = rulesetNodes.length;
            if (rulesetNodeCnt) {
                if (ruleNodes.length && sep) {
                    output.add(sep);
                }
                rulesetNodes[0].genCSS(env, output);
                for (i = 1; i < rulesetNodeCnt; i++) {
                    if (sep) {
                        output.add(sep);
                    }
                    rulesetNodes[i].genCSS(env, output);
                }
            }

            if (!output.isEmpty() && !env.compress && this.firstRoot) {
                output.add('\n');
            }
        },

        toCSS: tree.toCSS,

        markReferenced: function () {
            if (!this.selectors) {
                return;
            }
            for (var s = 0; s < this.selectors.length; s++) {
                this.selectors[s].markReferenced();
            }
        },

        joinSelectors: function (paths, context, selectors) {
            for (var s = 0; s < selectors.length; s++) {
                this.joinSelector(paths, context, selectors[s]);
            }
        },

        joinSelector: function (paths, context, selector) {

            var i, j, k,
                hasParentSelector, newSelectors, el, sel, parentSel,
                newSelectorPath, afterParentJoin, newJoinedSelector,
                newJoinedSelectorEmpty, lastSelector, currentElements,
                selectorsMultiplied;

            for (i = 0; i < selector.elements.length; i++) {
                el = selector.elements[i];
                if (el.value === '&') {
                    hasParentSelector = true;
                }
            }

            if (!hasParentSelector) {
                if (context.length > 0) {
                    for (i = 0; i < context.length; i++) {
                        paths.push(context[i].concat(selector));
                    }
                }
                else {
                    paths.push([selector]);
                }
                return;
            }

            // The paths are [[Selector]]
            // The first list is a list of comma seperated selectors
            // The inner list is a list of inheritance seperated selectors
            // e.g.
            // .a, .b {
            //   .c {
            //   }
            // }
            // == [[.a] [.c]] [[.b] [.c]]
            //

            // the elements from the current selector so far
            currentElements = [];
            // the current list of new selectors to add to the path.
            // We will build it up. We initiate it with one empty selector as we "multiply" the new selectors
            // by the parents
            newSelectors = [[]];

            for (i = 0; i < selector.elements.length; i++) {
                el = selector.elements[i];
                // non parent reference elements just get added
                if (el.value !== "&") {
                    currentElements.push(el);
                } else {
                    // the new list of selectors to add
                    selectorsMultiplied = [];

                    // merge the current list of non parent selector elements
                    // on to the current list of selectors to add
                    if (currentElements.length > 0) {
                        this.mergeElementsOnToSelectors(currentElements, newSelectors);
                    }

                    // loop through our current selectors
                    for (j = 0; j < newSelectors.length; j++) {
                        sel = newSelectors[j];
                        // if we don't have any parent paths, the & might be in a mixin so that it can be used
                        // whether there are parents or not
                        if (context.length === 0) {
                            // the combinator used on el should now be applied to the next element instead so that
                            // it is not lost
                            if (sel.length > 0) {
                                sel[0].elements = sel[0].elements.slice(0);
                                sel[0].elements.push(new (tree.Element)(el.combinator, '', el.index, el.currentFileInfo));
                            }
                            selectorsMultiplied.push(sel);
                        }
                        else {
                            // and the parent selectors
                            for (k = 0; k < context.length; k++) {
                                parentSel = context[k];
                                // We need to put the current selectors
                                // then join the last selector's elements on to the parents selectors

                                // our new selector path
                                newSelectorPath = [];
                                // selectors from the parent after the join
                                afterParentJoin = [];
                                newJoinedSelectorEmpty = true;

                                //construct the joined selector - if & is the first thing this will be empty,
                                // if not newJoinedSelector will be the last set of elements in the selector
                                if (sel.length > 0) {
                                    newSelectorPath = sel.slice(0);
                                    lastSelector = newSelectorPath.pop();
                                    newJoinedSelector = selector.createDerived(lastSelector.elements.slice(0));
                                    newJoinedSelectorEmpty = false;
                                }
                                else {
                                    newJoinedSelector = selector.createDerived([]);
                                }

                                //put together the parent selectors after the join
                                if (parentSel.length > 1) {
                                    afterParentJoin = afterParentJoin.concat(parentSel.slice(1));
                                }

                                if (parentSel.length > 0) {
                                    newJoinedSelectorEmpty = false;

                                    // join the elements so far with the first part of the parent
                                    newJoinedSelector.elements.push(new (tree.Element)(el.combinator, parentSel[0].elements[0].value, el.index, el.currentFileInfo));
                                    newJoinedSelector.elements = newJoinedSelector.elements.concat(parentSel[0].elements.slice(1));
                                }

                                if (!newJoinedSelectorEmpty) {
                                    // now add the joined selector
                                    newSelectorPath.push(newJoinedSelector);
                                }

                                // and the rest of the parent
                                newSelectorPath = newSelectorPath.concat(afterParentJoin);

                                // add that to our new set of selectors
                                selectorsMultiplied.push(newSelectorPath);
                            }
                        }
                    }

                    // our new selectors has been multiplied, so reset the state
                    newSelectors = selectorsMultiplied;
                    currentElements = [];
                }
            }

            // if we have any elements left over (e.g. .a& .b == .b)
            // add them on to all the current selectors
            if (currentElements.length > 0) {
                this.mergeElementsOnToSelectors(currentElements, newSelectors);
            }

            for (i = 0; i < newSelectors.length; i++) {
                if (newSelectors[i].length > 0) {
                    paths.push(newSelectors[i]);
                }
            }
        },

        mergeElementsOnToSelectors: function (elements, selectors) {
            var i, sel;

            if (selectors.length === 0) {
                selectors.push([new (tree.Selector)(elements)]);
                return;
            }

            for (i = 0; i < selectors.length; i++) {
                sel = selectors[i];

                // if the previous thing in sel is a parent this needs to join on to it
                if (sel.length > 0) {
                    sel[sel.length - 1] = sel[sel.length - 1].createDerived(sel[sel.length - 1].elements.concat(elements));
                }
                else {
                    sel.push(new (tree.Selector)(elements));
                }
            }
        }
    };
})(require('../tree'));

(function (tree) {

    tree.Selector = function (elements, extendList, condition, index, currentFileInfo, isReferenced) {
        this.elements = elements;
        this.extendList = extendList;
        this.condition = condition;
        this.currentFileInfo = currentFileInfo || {};
        this.isReferenced = isReferenced;
        if (!condition) {
            this.evaldCondition = true;
        }
    };
    tree.Selector.prototype = {
        type: "Selector",
        accept: function (visitor) {
            if (this.elements) {
                this.elements = visitor.visitArray(this.elements);
            }
            if (this.extendList) {
                this.extendList = visitor.visitArray(this.extendList);
            }
            if (this.condition) {
                this.condition = visitor.visit(this.condition);
            }
        },
        createDerived: function (elements, extendList, evaldCondition) {
            evaldCondition = (evaldCondition != null) ? evaldCondition : this.evaldCondition;
            var newSelector = new (tree.Selector)(elements, extendList || this.extendList, null, this.index, this.currentFileInfo, this.isReferenced);
            newSelector.evaldCondition = evaldCondition;
            newSelector.mediaEmpty = this.mediaEmpty;
            return newSelector;
        },
        match: function (other) {
            var elements = this.elements,
                len = elements.length,
                olen, i;

            other.CacheElements();

            olen = other._elements.length;
            if (olen === 0 || len < olen) {
                return 0;
            } else {
                for (i = 0; i < olen; i++) {
                    if (elements[i].value !== other._elements[i]) {
                        return 0;
                    }
                }
            }

            return olen; // return number of matched elements
        },
        CacheElements: function () {
            var css = '', len, v, i;

            if (!this._elements) {

                len = this.elements.length;
                for (i = 0; i < len; i++) {

                    v = this.elements[i];
                    css += v.combinator.value;

                    if (!v.value.value) {
                        css += v.value;
                        continue;
                    }

                    if (typeof v.value.value !== "string") {
                        css = '';
                        break;
                    }
                    css += v.value.value;
                }

                this._elements = css.match(/[,&#\*\.\w-]([\w-]|(\\.))*/g);

                if (this._elements) {
                    if (this._elements[0] === "&") {
                        this._elements.shift();
                    }

                } else {
                    this._elements = [];
                }

            }
        },
        isJustParentSelector: function () {
            return !this.mediaEmpty &&
                this.elements.length === 1 &&
                this.elements[0].value === '&' &&
                (this.elements[0].combinator.value === ' ' || this.elements[0].combinator.value === '');
        },
        eval: function (env) {
            var evaldCondition = this.condition && this.condition.eval(env),
                elements = this.elements, extendList = this.extendList;

            elements = elements && elements.map(function (e) {
                return e.eval(env);
            });
            extendList = extendList && extendList.map(function (extend) {
                return extend.eval(env);
            });

            return this.createDerived(elements, extendList, evaldCondition);
        },
        genCSS: function (env, output) {
            var i, element;
            if ((!env || !env.firstSelector) && this.elements[0].combinator.value === "") {
                output.add(' ', this.currentFileInfo, this.index);
            }
            if (!this._css) {
                //TODO caching? speed comparison?
                for (i = 0; i < this.elements.length; i++) {
                    element = this.elements[i];
                    element.genCSS(env, output);
                }
            }
        },
        toCSS: tree.toCSS,
        markReferenced: function () {
            this.isReferenced = true;
        },
        getIsReferenced: function () {
            return !this.currentFileInfo.reference || this.isReferenced;
        },
        getIsOutput: function () {
            return this.evaldCondition;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.UnicodeDescriptor = function (value) {
        this.value = value;
    };
    tree.UnicodeDescriptor.prototype = {
        type: "UnicodeDescriptor",
        genCSS: function (env, output) {
            output.add(this.value);
        },
        toCSS: tree.toCSS,
        eval: function () {
            return this;
        }
    };

})(require('../tree'));

(function (tree) {

    tree.URL = function (val, currentFileInfo, isEvald) {
        this.value = val;
        this.currentFileInfo = currentFileInfo;
        this.isEvald = isEvald;
    };
    tree.URL.prototype = {
        type: "Url",
        accept: function (visitor) {
            this.value = visitor.visit(this.value);
        },
        genCSS: function (env, output) {
            output.add("url(");
            this.value.genCSS(env, output);
            output.add(")");
        },
        toCSS: tree.toCSS,
        eval: function (ctx) {
            var val = this.value.eval(ctx),
                rootpath;

            if (!this.isEvald) {
                // Add the base path if the URL is relative
                rootpath = this.currentFileInfo && this.currentFileInfo.rootpath;
                if (rootpath && typeof val.value === "string" && ctx.isPathRelative(val.value)) {
                    if (!val.quote) {
                        rootpath = rootpath.replace(/[\(\)'"\s]/g, function (match) {
                            return "\\" + match;
                        });
                    }
                    val.value = rootpath + val.value;
                }

                val.value = ctx.normalizePath(val.value);

                // Add url args if enabled
                if (ctx.urlArgs) {
                    if (!val.value.match(/^\s*data:/)) {
                        var delimiter = val.value.indexOf('?') === -1 ? '?' : '&';
                        var urlArgs = delimiter + ctx.urlArgs;
                        if (val.value.indexOf('#') !== -1) {
                            val.value = val.value.replace('#', urlArgs + '#');
                        } else {
                            val.value += urlArgs;
                        }
                    }
                }
            }

            return new (tree.URL)(val, this.currentFileInfo, true);
        }
    };

})(require('../tree'));

(function (tree) {

    tree.Value = function (value) {
        this.value = value;
    };
    tree.Value.prototype = {
        type: "Value",
        accept: function (visitor) {
            if (this.value) {
                this.value = visitor.visitArray(this.value);
            }
        },
        eval: function (env) {
            if (this.value.length === 1) {
                return this.value[0].eval(env);
            } else {
                return new (tree.Value)(this.value.map(function (v) {
                    return v.eval(env);
                }));
            }
        },
        genCSS: function (env, output) {
            var i;
            for (i = 0; i < this.value.length; i++) {
                this.value[i].genCSS(env, output);
                if (i + 1 < this.value.length) {
                    output.add((env && env.compress) ? ',' : ', ');
                }
            }
        },
        toCSS: tree.toCSS
    };

})(require('../tree'));

(function (tree) {

    tree.Variable = function (name, index, currentFileInfo) {
        this.name = name;
        this.index = index;
        this.currentFileInfo = currentFileInfo || {};
    };
    tree.Variable.prototype = {
        type: "Variable",
        eval: function (env) {
            var variable, name = this.name;

            if (name.indexOf('@@') === 0) {
                name = '@' + new (tree.Variable)(name.slice(1)).eval(env).value;
            }

            if (this.evaluating) {
                throw {
                    type: 'Name',
                    message: "Recursive variable definition for " + name,
                    filename: this.currentFileInfo.file,
                    index: this.index
                };
            }

            this.evaluating = true;

            variable = tree.find(env.frames, function (frame) {
                var v = frame.variable(name);
                if (v) {
                    return v.value.eval(env);
                }
            });
            if (variable) {
                this.evaluating = false;
                return variable;
            } else {
                throw {
                    type: 'Name',
                    message: "variable " + name + " is undefined",
                    filename: this.currentFileInfo.filename,
                    index: this.index
                };
            }
        }
    };

})(require('../tree'));

(function (tree) {

    var parseCopyProperties = [
        'paths',            // option - unmodified - paths to search for imports on
        'optimization',     // option - optimization level (for the chunker)
        'files',            // list of files that have been imported, used for import-once
        'contents',         // map - filename to contents of all the files
        'contentsIgnoredChars', // map - filename to lines at the begining of each file to ignore
        'relativeUrls',     // option - whether to adjust URL's to be relative
        'rootpath',         // option - rootpath to append to URL's
        'strictImports',    // option -
        'insecure',         // option - whether to allow imports from insecure ssl hosts
        'dumpLineNumbers',  // option - whether to dump line numbers
        'compress',         // option - whether to compress
        'processImports',   // option - whether to process imports. if false then imports will not be imported
        'syncImport',       // option - whether to import synchronously
        'javascriptEnabled',// option - whether JavaScript is enabled. if undefined, defaults to true
        'mime',             // browser only - mime type for sheet import
        'useFileCache',     // browser only - whether to use the per file session cache
        'currentFileInfo'   // information about the current file - for error reporting and importing and making urls relative etc.
    ];

    //currentFileInfo = {
    //  'relativeUrls' - option - whether to adjust URL's to be relative
    //  'filename' - full resolved filename of current file
    //  'rootpath' - path to append to normal URLs for this node
    //  'currentDirectory' - path to the current file, absolute
    //  'rootFilename' - filename of the base file
    //  'entryPath' - absolute path to the entry file
    //  'reference' - whether the file should not be output and only output parts that are referenced

    tree.parseEnv = function (options) {
        copyFromOriginal(options, this, parseCopyProperties);

        if (!this.contents) {
            this.contents = {};
        }
        if (!this.contentsIgnoredChars) {
            this.contentsIgnoredChars = {};
        }
        if (!this.files) {
            this.files = {};
        }

        if (typeof this.paths === "string") {
            this.paths = [this.paths];
        }

        if (!this.currentFileInfo) {
            var filename = (options && options.filename) || "input";
            var entryPath = filename.replace(/[^\/\\]*$/, "");
            if (options) {
                options.filename = null;
            }
            this.currentFileInfo = {
                filename: filename,
                relativeUrls: this.relativeUrls,
                rootpath: (options && options.rootpath) || "",
                currentDirectory: entryPath,
                entryPath: entryPath,
                rootFilename: filename
            };
        }
    };

    var evalCopyProperties = [
        'silent',         // whether to swallow errors and warnings
        'verbose',        // whether to log more activity
        'compress',       // whether to compress
        'yuicompress',    // whether to compress with the outside tool yui compressor
        'ieCompat',       // whether to enforce IE compatibility (IE8 data-uri)
        'strictMath',     // whether math has to be within parenthesis
        'strictUnits',    // whether units need to evaluate correctly
        'cleancss',       // whether to compress with clean-css
        'sourceMap',      // whether to output a source map
        'importMultiple', // whether we are currently importing multiple copies
        'urlArgs'         // whether to add args into url tokens
    ];

    tree.evalEnv = function (options, frames) {
        copyFromOriginal(options, this, evalCopyProperties);

        this.frames = frames || [];
    };

    tree.evalEnv.prototype.inParenthesis = function () {
        if (!this.parensStack) {
            this.parensStack = [];
        }
        this.parensStack.push(true);
    };

    tree.evalEnv.prototype.outOfParenthesis = function () {
        this.parensStack.pop();
    };

    tree.evalEnv.prototype.isMathOn = function () {
        return this.strictMath ? (this.parensStack && this.parensStack.length) : true;
    };

    tree.evalEnv.prototype.isPathRelative = function (path) {
        return !/^(?:[a-z-]+:|\/)/.test(path);
    };

    tree.evalEnv.prototype.normalizePath = function (path) {
        var
            segments = path.split("/").reverse(),
            segment;

        path = [];
        while (segments.length !== 0) {
            segment = segments.pop();
            switch (segment) {
                case ".":
                    break;
                case "..":
                    if ((path.length === 0) || (path[path.length - 1] === "..")) {
                        path.push(segment);
                    } else {
                        path.pop();
                    }
                    break;
                default:
                    path.push(segment);
                    break;
            }
        }

        return path.join("/");
    };

    //todo - do the same for the toCSS env
    //tree.toCSSEnv = function (options) {
    //};

    var copyFromOriginal = function (original, destination, propertiesToCopy) {
        if (!original) {
            return;
        }

        for (var i = 0; i < propertiesToCopy.length; i++) {
            if (original.hasOwnProperty(propertiesToCopy[i])) {
                destination[propertiesToCopy[i]] = original[propertiesToCopy[i]];
            }
        }
    };

})(require('./tree'));

(function (tree) {

    var _visitArgs = {visitDeeper: true},
        _hasIndexed = false;

    function _noop(node) {
        return node;
    }

    function indexNodeTypes(parent, ticker) {
        // add .typeIndex to tree node types for lookup table
        var key, child;
        for (key in parent) {
            if (parent.hasOwnProperty(key)) {
                child = parent[key];
                switch (typeof child) {
                    case "function":
                        // ignore bound functions directly on tree which do not have a prototype
                        // or aren't nodes
                        if (child.prototype && child.prototype.type) {
                            child.prototype.typeIndex = ticker++;
                        }
                        break;
                    case "object":
                        ticker = indexNodeTypes(child, ticker);
                        break;
                }
            }
        }
        return ticker;
    }

    tree.visitor = function (implementation) {
        this._implementation = implementation;
        this._visitFnCache = [];

        if (!_hasIndexed) {
            indexNodeTypes(tree, 1);
            _hasIndexed = true;
        }
    };

    tree.visitor.prototype = {
        visit: function (node) {
            if (!node) {
                return node;
            }

            var nodeTypeIndex = node.typeIndex;
            if (!nodeTypeIndex) {
                return node;
            }

            var visitFnCache = this._visitFnCache,
                impl = this._implementation,
                aryIndx = nodeTypeIndex << 1,
                outAryIndex = aryIndx | 1,
                func = visitFnCache[aryIndx],
                funcOut = visitFnCache[outAryIndex],
                visitArgs = _visitArgs,
                fnName;

            visitArgs.visitDeeper = true;

            if (!func) {
                fnName = "visit" + node.type;
                func = impl[fnName] || _noop;
                funcOut = impl[fnName + "Out"] || _noop;
                visitFnCache[aryIndx] = func;
                visitFnCache[outAryIndex] = funcOut;
            }

            if (func !== _noop) {
                var newNode = func.call(impl, node, visitArgs);
                if (impl.isReplacing) {
                    node = newNode;
                }
            }

            if (visitArgs.visitDeeper && node && node.accept) {
                node.accept(this);
            }

            if (funcOut != _noop) {
                funcOut.call(impl, node);
            }

            return node;
        },
        visitArray: function (nodes, nonReplacing) {
            if (!nodes) {
                return nodes;
            }

            var cnt = nodes.length, i;

            // Non-replacing
            if (nonReplacing || !this._implementation.isReplacing) {
                for (i = 0; i < cnt; i++) {
                    this.visit(nodes[i]);
                }
                return nodes;
            }

            // Replacing
            var out = [];
            for (i = 0; i < cnt; i++) {
                var evald = this.visit(nodes[i]);
                if (!evald.splice) {
                    out.push(evald);
                } else if (evald.length) {
                    this.flatten(evald, out);
                }
            }
            return out;
        },
        flatten: function (arr, out) {
            if (!out) {
                out = [];
            }

            var cnt, i, item,
                nestedCnt, j, nestedItem;

            for (i = 0, cnt = arr.length; i < cnt; i++) {
                item = arr[i];
                if (!item.splice) {
                    out.push(item);
                    continue;
                }

                for (j = 0, nestedCnt = item.length; j < nestedCnt; j++) {
                    nestedItem = item[j];
                    if (!nestedItem.splice) {
                        out.push(nestedItem);
                    } else if (nestedItem.length) {
                        this.flatten(nestedItem, out);
                    }
                }
            }

            return out;
        }
    };

})(require('./tree'));
(function (tree) {
    tree.importVisitor = function (importer, finish, evalEnv, onceFileDetectionMap, recursionDetector) {
        this._visitor = new tree.visitor(this);
        this._importer = importer;
        this._finish = finish;
        this.env = evalEnv || new tree.evalEnv();
        this.importCount = 0;
        this.onceFileDetectionMap = onceFileDetectionMap || {};
        this.recursionDetector = {};
        if (recursionDetector) {
            for (var fullFilename in recursionDetector) {
                if (recursionDetector.hasOwnProperty(fullFilename)) {
                    this.recursionDetector[fullFilename] = true;
                }
            }
        }
    };

    tree.importVisitor.prototype = {
        isReplacing: true,
        run: function (root) {
            var error;
            try {
                // process the contents
                this._visitor.visit(root);
            }
            catch (e) {
                error = e;
            }

            this.isFinished = true;

            if (this.importCount === 0) {
                this._finish(error);
            }
        },
        visitImport: function (importNode, visitArgs) {
            var importVisitor = this,
                evaldImportNode,
                inlineCSS = importNode.options.inline;

            if (!importNode.css || inlineCSS) {

                try {
                    evaldImportNode = importNode.evalForImport(this.env);
                } catch (e) {
                    if (!e.filename) {
                        e.index = importNode.index;
                        e.filename = importNode.currentFileInfo.filename;
                    }
                    // attempt to eval properly and treat as css
                    importNode.css = true;
                    // if that fails, this error will be thrown
                    importNode.error = e;
                }

                if (evaldImportNode && (!evaldImportNode.css || inlineCSS)) {
                    importNode = evaldImportNode;
                    this.importCount++;
                    var env = new tree.evalEnv(this.env, this.env.frames.slice(0));

                    if (importNode.options.multiple) {
                        env.importMultiple = true;
                    }

                    this._importer.push(importNode.getPath(), importNode.currentFileInfo, importNode.options, function (e, root, importedAtRoot, fullPath) {
                        if (e && !e.filename) {
                            e.index = importNode.index;
                            e.filename = importNode.currentFileInfo.filename;
                        }

                        var duplicateImport = importedAtRoot || fullPath in importVisitor.recursionDetector;
                        if (!env.importMultiple) {
                            if (duplicateImport) {
                                importNode.skip = true;
                            } else {
                                importNode.skip = function () {
                                    if (fullPath in importVisitor.onceFileDetectionMap) {
                                        return true;
                                    }
                                    importVisitor.onceFileDetectionMap[fullPath] = true;
                                    return false;
                                };
                            }
                        }

                        var subFinish = function (e) {
                            importVisitor.importCount--;

                            if (importVisitor.importCount === 0 && importVisitor.isFinished) {
                                importVisitor._finish(e);
                            }
                        };

                        if (root) {
                            importNode.root = root;
                            importNode.importedFilename = fullPath;

                            if (!inlineCSS && (env.importMultiple || !duplicateImport)) {
                                importVisitor.recursionDetector[fullPath] = true;
                                new (tree.importVisitor)(importVisitor._importer, subFinish, env, importVisitor.onceFileDetectionMap, importVisitor.recursionDetector)
                                    .run(root);
                                return;
                            }
                        }

                        subFinish();
                    });
                }
            }
            visitArgs.visitDeeper = false;
            return importNode;
        },
        visitRule: function (ruleNode, visitArgs) {
            visitArgs.visitDeeper = false;
            return ruleNode;
        },
        visitDirective: function (directiveNode, visitArgs) {
            this.env.frames.unshift(directiveNode);
            return directiveNode;
        },
        visitDirectiveOut: function (directiveNode) {
            this.env.frames.shift();
        },
        visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
            this.env.frames.unshift(mixinDefinitionNode);
            return mixinDefinitionNode;
        },
        visitMixinDefinitionOut: function (mixinDefinitionNode) {
            this.env.frames.shift();
        },
        visitRuleset: function (rulesetNode, visitArgs) {
            this.env.frames.unshift(rulesetNode);
            return rulesetNode;
        },
        visitRulesetOut: function (rulesetNode) {
            this.env.frames.shift();
        },
        visitMedia: function (mediaNode, visitArgs) {
            this.env.frames.unshift(mediaNode.rules[0]);
            return mediaNode;
        },
        visitMediaOut: function (mediaNode) {
            this.env.frames.shift();
        }
    };

})(require('./tree'));
(function (tree) {
    tree.joinSelectorVisitor = function () {
        this.contexts = [[]];
        this._visitor = new tree.visitor(this);
    };

    tree.joinSelectorVisitor.prototype = {
        run: function (root) {
            return this._visitor.visit(root);
        },
        visitRule: function (ruleNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },

        visitRuleset: function (rulesetNode, visitArgs) {
            var context = this.contexts[this.contexts.length - 1],
                paths = [], selectors;

            this.contexts.push(paths);

            if (!rulesetNode.root) {
                selectors = rulesetNode.selectors;
                if (selectors) {
                    selectors = selectors.filter(function (selector) {
                        return selector.getIsOutput();
                    });
                    rulesetNode.selectors = selectors.length ? selectors : (selectors = null);
                    if (selectors) {
                        rulesetNode.joinSelectors(paths, context, selectors);
                    }
                }
                if (!selectors) {
                    rulesetNode.rules = null;
                }
                rulesetNode.paths = paths;
            }
        },
        visitRulesetOut: function (rulesetNode) {
            this.contexts.length = this.contexts.length - 1;
        },
        visitMedia: function (mediaNode, visitArgs) {
            var context = this.contexts[this.contexts.length - 1];
            mediaNode.rules[0].root = (context.length === 0 || context[0].multiMedia);
        }
    };

})(require('./tree'));
(function (tree) {
    tree.toCSSVisitor = function (env) {
        this._visitor = new tree.visitor(this);
        this._env = env;
    };

    tree.toCSSVisitor.prototype = {
        isReplacing: true,
        run: function (root) {
            return this._visitor.visit(root);
        },

        visitRule: function (ruleNode, visitArgs) {
            if (ruleNode.variable) {
                return [];
            }
            return ruleNode;
        },

        visitMixinDefinition: function (mixinNode, visitArgs) {
            // mixin definitions do not get eval'd - this means they keep state
            // so we have to clear that state here so it isn't used if toCSS is called twice
            mixinNode.frames = [];
            return [];
        },

        visitExtend: function (extendNode, visitArgs) {
            return [];
        },

        visitComment: function (commentNode, visitArgs) {
            if (commentNode.isSilent(this._env)) {
                return [];
            }
            return commentNode;
        },

        visitMedia: function (mediaNode, visitArgs) {
            mediaNode.accept(this._visitor);
            visitArgs.visitDeeper = false;

            if (!mediaNode.rules.length) {
                return [];
            }
            return mediaNode;
        },

        visitDirective: function (directiveNode, visitArgs) {
            if (directiveNode.currentFileInfo.reference && !directiveNode.isReferenced) {
                return [];
            }
            if (directiveNode.name === "@charset") {
                // Only output the debug info together with subsequent @charset definitions
                // a comment (or @media statement) before the actual @charset directive would
                // be considered illegal css as it has to be on the first line
                if (this.charset) {
                    if (directiveNode.debugInfo) {
                        var comment = new tree.Comment("/* " + directiveNode.toCSS(this._env).replace(/\n/g, "") + " */\n");
                        comment.debugInfo = directiveNode.debugInfo;
                        return this._visitor.visit(comment);
                    }
                    return [];
                }
                this.charset = true;
            }
            if (directiveNode.rules && directiveNode.rules.rules) {
                this._mergeRules(directiveNode.rules.rules);
            }
            return directiveNode;
        },

        checkPropertiesInRoot: function (rules) {
            var ruleNode;
            for (var i = 0; i < rules.length; i++) {
                ruleNode = rules[i];
                if (ruleNode instanceof tree.Rule && !ruleNode.variable) {
                    throw {
                        message: "properties must be inside selector blocks, they cannot be in the root.",
                        index: ruleNode.index,
                        filename: ruleNode.currentFileInfo ? ruleNode.currentFileInfo.filename : null
                    };
                }
            }
        },

        visitRuleset: function (rulesetNode, visitArgs) {
            var rule, rulesets = [];
            if (rulesetNode.firstRoot) {
                this.checkPropertiesInRoot(rulesetNode.rules);
            }
            if (!rulesetNode.root) {
                if (rulesetNode.paths) {
                    rulesetNode.paths = rulesetNode.paths
                        .filter(function (p) {
                            var i;
                            if (p[0].elements[0].combinator.value === ' ') {
                                p[0].elements[0].combinator = new (tree.Combinator)('');
                            }
                            for (i = 0; i < p.length; i++) {
                                if (p[i].getIsReferenced() && p[i].getIsOutput()) {
                                    return true;
                                }
                            }
                            return false;
                        });
                }

                // Compile rules and rulesets
                var nodeRules = rulesetNode.rules, nodeRuleCnt = nodeRules ? nodeRules.length : 0;
                for (var i = 0; i < nodeRuleCnt;) {
                    rule = nodeRules[i];
                    if (rule && rule.rules) {
                        // visit because we are moving them out from being a child
                        rulesets.push(this._visitor.visit(rule));
                        nodeRules.splice(i, 1);
                        nodeRuleCnt--;
                        continue;
                    }
                    i++;
                }
                // accept the visitor to remove rules and refactor itself
                // then we can decide now whether we want it or not
                if (nodeRuleCnt > 0) {
                    rulesetNode.accept(this._visitor);
                } else {
                    rulesetNode.rules = null;
                }
                visitArgs.visitDeeper = false;

                nodeRules = rulesetNode.rules;
                if (nodeRules) {
                    this._mergeRules(nodeRules);
                    nodeRules = rulesetNode.rules;
                }
                if (nodeRules) {
                    this._removeDuplicateRules(nodeRules);
                    nodeRules = rulesetNode.rules;
                }

                // now decide whether we keep the ruleset
                if (nodeRules && nodeRules.length > 0 && rulesetNode.paths.length > 0) {
                    rulesets.splice(0, 0, rulesetNode);
                }
            } else {
                rulesetNode.accept(this._visitor);
                visitArgs.visitDeeper = false;
                if (rulesetNode.firstRoot || (rulesetNode.rules && rulesetNode.rules.length > 0)) {
                    rulesets.splice(0, 0, rulesetNode);
                }
            }
            if (rulesets.length === 1) {
                return rulesets[0];
            }
            return rulesets;
        },

        _removeDuplicateRules: function (rules) {
            if (!rules) {
                return;
            }

            // remove duplicates
            var ruleCache = {},
                ruleList, rule, i;

            for (i = rules.length - 1; i >= 0; i--) {
                rule = rules[i];
                if (rule instanceof tree.Rule) {
                    if (!ruleCache[rule.name]) {
                        ruleCache[rule.name] = rule;
                    } else {
                        ruleList = ruleCache[rule.name];
                        if (ruleList instanceof tree.Rule) {
                            ruleList = ruleCache[rule.name] = [ruleCache[rule.name].toCSS(this._env)];
                        }
                        var ruleCSS = rule.toCSS(this._env);
                        if (ruleList.indexOf(ruleCSS) !== -1) {
                            rules.splice(i, 1);
                        } else {
                            ruleList.push(ruleCSS);
                        }
                    }
                }
            }
        },

        _mergeRules: function (rules) {
            if (!rules) {
                return;
            }

            var groups = {},
                parts,
                rule,
                key;

            for (var i = 0; i < rules.length; i++) {
                rule = rules[i];

                if ((rule instanceof tree.Rule) && rule.merge) {
                    key = [rule.name,
                        rule.important ? "!" : ""].join(",");

                    if (!groups[key]) {
                        groups[key] = [];
                    } else {
                        rules.splice(i--, 1);
                    }

                    groups[key].push(rule);
                }
            }

            Object.keys(groups).map(function (k) {

                function toExpression(values) {
                    return new (tree.Expression)(values.map(function (p) {
                        return p.value;
                    }));
                }

                function toValue(values) {
                    return new (tree.Value)(values.map(function (p) {
                        return p;
                    }));
                }

                parts = groups[k];

                if (parts.length > 1) {
                    rule = parts[0];
                    var spacedGroups = [];
                    var lastSpacedGroup = [];
                    parts.map(function (p) {
                        if (p.merge === "+") {
                            if (lastSpacedGroup.length > 0) {
                                spacedGroups.push(toExpression(lastSpacedGroup));
                            }
                            lastSpacedGroup = [];
                        }
                        lastSpacedGroup.push(p);
                    });
                    spacedGroups.push(toExpression(lastSpacedGroup));
                    rule.value = toValue(spacedGroups);
                }
            });
        }
    };

})(require('./tree'));
(function (tree) {
    /*jshint loopfunc:true */

    tree.extendFinderVisitor = function () {
        this._visitor = new tree.visitor(this);
        this.contexts = [];
        this.allExtendsStack = [[]];
    };

    tree.extendFinderVisitor.prototype = {
        run: function (root) {
            root = this._visitor.visit(root);
            root.allExtends = this.allExtendsStack[0];
            return root;
        },
        visitRule: function (ruleNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitRuleset: function (rulesetNode, visitArgs) {
            if (rulesetNode.root) {
                return;
            }

            var i, j, extend, allSelectorsExtendList = [], extendList;

            // get &:extend(.a); rules which apply to all selectors in this ruleset
            var rules = rulesetNode.rules, ruleCnt = rules ? rules.length : 0;
            for (i = 0; i < ruleCnt; i++) {
                if (rulesetNode.rules[i] instanceof tree.Extend) {
                    allSelectorsExtendList.push(rules[i]);
                    rulesetNode.extendOnEveryPath = true;
                }
            }

            // now find every selector and apply the extends that apply to all extends
            // and the ones which apply to an individual extend
            var paths = rulesetNode.paths;
            for (i = 0; i < paths.length; i++) {
                var selectorPath = paths[i],
                    selector = selectorPath[selectorPath.length - 1],
                    selExtendList = selector.extendList;

                extendList = selExtendList ? selExtendList.slice(0).concat(allSelectorsExtendList)
                    : allSelectorsExtendList;

                if (extendList) {
                    extendList = extendList.map(function (allSelectorsExtend) {
                        return allSelectorsExtend.clone();
                    });
                }

                for (j = 0; j < extendList.length; j++) {
                    this.foundExtends = true;
                    extend = extendList[j];
                    extend.findSelfSelectors(selectorPath);
                    extend.ruleset = rulesetNode;
                    if (j === 0) {
                        extend.firstExtendOnThisSelectorPath = true;
                    }
                    this.allExtendsStack[this.allExtendsStack.length - 1].push(extend);
                }
            }

            this.contexts.push(rulesetNode.selectors);
        },
        visitRulesetOut: function (rulesetNode) {
            if (!rulesetNode.root) {
                this.contexts.length = this.contexts.length - 1;
            }
        },
        visitMedia: function (mediaNode, visitArgs) {
            mediaNode.allExtends = [];
            this.allExtendsStack.push(mediaNode.allExtends);
        },
        visitMediaOut: function (mediaNode) {
            this.allExtendsStack.length = this.allExtendsStack.length - 1;
        },
        visitDirective: function (directiveNode, visitArgs) {
            directiveNode.allExtends = [];
            this.allExtendsStack.push(directiveNode.allExtends);
        },
        visitDirectiveOut: function (directiveNode) {
            this.allExtendsStack.length = this.allExtendsStack.length - 1;
        }
    };

    tree.processExtendsVisitor = function () {
        this._visitor = new tree.visitor(this);
    };

    tree.processExtendsVisitor.prototype = {
        run: function (root) {
            var extendFinder = new tree.extendFinderVisitor();
            extendFinder.run(root);
            if (!extendFinder.foundExtends) {
                return root;
            }
            root.allExtends = root.allExtends.concat(this.doExtendChaining(root.allExtends, root.allExtends));
            this.allExtendsStack = [root.allExtends];
            return this._visitor.visit(root);
        },
        doExtendChaining: function (extendsList, extendsListTarget, iterationCount) {
            //
            // chaining is different from normal extension.. if we extend an extend then we are not just copying, altering and pasting
            // the selector we would do normally, but we are also adding an extend with the same target selector
            // this means this new extend can then go and alter other extends
            //
            // this method deals with all the chaining work - without it, extend is flat and doesn't work on other extend selectors
            // this is also the most expensive.. and a match on one selector can cause an extension of a selector we had already processed if
            // we look at each selector at a time, as is done in visitRuleset

            var extendIndex, targetExtendIndex, matches, extendsToAdd = [], newSelector, extendVisitor = this, selectorPath, extend, targetExtend, newExtend;

            iterationCount = iterationCount || 0;

            //loop through comparing every extend with every target extend.
            // a target extend is the one on the ruleset we are looking at copy/edit/pasting in place
            // e.g.  .a:extend(.b) {}  and .b:extend(.c) {} then the first extend extends the second one
            // and the second is the target.
            // the seperation into two lists allows us to process a subset of chains with a bigger set, as is the
            // case when processing media queries
            for (extendIndex = 0; extendIndex < extendsList.length; extendIndex++) {
                for (targetExtendIndex = 0; targetExtendIndex < extendsListTarget.length; targetExtendIndex++) {

                    extend = extendsList[extendIndex];
                    targetExtend = extendsListTarget[targetExtendIndex];

                    // look for circular references
                    if (extend.parent_ids.indexOf(targetExtend.object_id) >= 0) {
                        continue;
                    }

                    // find a match in the target extends self selector (the bit before :extend)
                    selectorPath = [targetExtend.selfSelectors[0]];
                    matches = extendVisitor.findMatch(extend, selectorPath);

                    if (matches.length) {

                        // we found a match, so for each self selector..
                        extend.selfSelectors.forEach(function (selfSelector) {

                            // process the extend as usual
                            newSelector = extendVisitor.extendSelector(matches, selectorPath, selfSelector);

                            // but now we create a new extend from it
                            newExtend = new (tree.Extend)(targetExtend.selector, targetExtend.option, 0);
                            newExtend.selfSelectors = newSelector;

                            // add the extend onto the list of extends for that selector
                            newSelector[newSelector.length - 1].extendList = [newExtend];

                            // record that we need to add it.
                            extendsToAdd.push(newExtend);
                            newExtend.ruleset = targetExtend.ruleset;

                            //remember its parents for circular references
                            newExtend.parent_ids = newExtend.parent_ids.concat(targetExtend.parent_ids, extend.parent_ids);

                            // only process the selector once.. if we have :extend(.a,.b) then multiple
                            // extends will look at the same selector path, so when extending
                            // we know that any others will be duplicates in terms of what is added to the css
                            if (targetExtend.firstExtendOnThisSelectorPath) {
                                newExtend.firstExtendOnThisSelectorPath = true;
                                targetExtend.ruleset.paths.push(newSelector);
                            }
                        });
                    }
                }
            }

            if (extendsToAdd.length) {
                // try to detect circular references to stop a stack overflow.
                // may no longer be needed.
                this.extendChainCount++;
                if (iterationCount > 100) {
                    var selectorOne = "{unable to calculate}";
                    var selectorTwo = "{unable to calculate}";
                    try {
                        selectorOne = extendsToAdd[0].selfSelectors[0].toCSS();
                        selectorTwo = extendsToAdd[0].selector.toCSS();
                    }
                    catch (e) {
                    }
                    throw {message: "extend circular reference detected. One of the circular extends is currently:" + selectorOne + ":extend(" + selectorTwo + ")"};
                }

                // now process the new extends on the existing rules so that we can handle a extending b extending c ectending d extending e...
                return extendsToAdd.concat(extendVisitor.doExtendChaining(extendsToAdd, extendsListTarget, iterationCount + 1));
            } else {
                return extendsToAdd;
            }
        },
        visitRule: function (ruleNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitSelector: function (selectorNode, visitArgs) {
            visitArgs.visitDeeper = false;
        },
        visitRuleset: function (rulesetNode, visitArgs) {
            if (rulesetNode.root) {
                return;
            }
            var matches, pathIndex, extendIndex, allExtends = this.allExtendsStack[this.allExtendsStack.length - 1], selectorsToAdd = [], extendVisitor = this, selectorPath;

            // look at each selector path in the ruleset, find any extend matches and then copy, find and replace

            for (extendIndex = 0; extendIndex < allExtends.length; extendIndex++) {
                for (pathIndex = 0; pathIndex < rulesetNode.paths.length; pathIndex++) {
                    selectorPath = rulesetNode.paths[pathIndex];

                    // extending extends happens initially, before the main pass
                    if (rulesetNode.extendOnEveryPath) {
                        continue;
                    }
                    var extendList = selectorPath[selectorPath.length - 1].extendList;
                    if (extendList && extendList.length) {
                        continue;
                    }

                    matches = this.findMatch(allExtends[extendIndex], selectorPath);

                    if (matches.length) {

                        allExtends[extendIndex].selfSelectors.forEach(function (selfSelector) {
                            selectorsToAdd.push(extendVisitor.extendSelector(matches, selectorPath, selfSelector));
                        });
                    }
                }
            }
            rulesetNode.paths = rulesetNode.paths.concat(selectorsToAdd);
        },
        findMatch: function (extend, haystackSelectorPath) {
            //
            // look through the haystack selector path to try and find the needle - extend.selector
            // returns an array of selector matches that can then be replaced
            //
            var haystackSelectorIndex, hackstackSelector, hackstackElementIndex, haystackElement,
                targetCombinator, i,
                extendVisitor = this,
                needleElements = extend.selector.elements,
                potentialMatches = [], potentialMatch, matches = [];

            // loop through the haystack elements
            for (haystackSelectorIndex = 0; haystackSelectorIndex < haystackSelectorPath.length; haystackSelectorIndex++) {
                hackstackSelector = haystackSelectorPath[haystackSelectorIndex];

                for (hackstackElementIndex = 0; hackstackElementIndex < hackstackSelector.elements.length; hackstackElementIndex++) {

                    haystackElement = hackstackSelector.elements[hackstackElementIndex];

                    // if we allow elements before our match we can add a potential match every time. otherwise only at the first element.
                    if (extend.allowBefore || (haystackSelectorIndex === 0 && hackstackElementIndex === 0)) {
                        potentialMatches.push({
                            pathIndex: haystackSelectorIndex,
                            index: hackstackElementIndex,
                            matched: 0,
                            initialCombinator: haystackElement.combinator
                        });
                    }

                    for (i = 0; i < potentialMatches.length; i++) {
                        potentialMatch = potentialMatches[i];

                        // selectors add " " onto the first element. When we use & it joins the selectors together, but if we don't
                        // then each selector in haystackSelectorPath has a space before it added in the toCSS phase. so we need to work out
                        // what the resulting combinator will be
                        targetCombinator = haystackElement.combinator.value;
                        if (targetCombinator === '' && hackstackElementIndex === 0) {
                            targetCombinator = ' ';
                        }

                        // if we don't match, null our match to indicate failure
                        if (!extendVisitor.isElementValuesEqual(needleElements[potentialMatch.matched].value, haystackElement.value) ||
                            (potentialMatch.matched > 0 && needleElements[potentialMatch.matched].combinator.value !== targetCombinator)) {
                            potentialMatch = null;
                        } else {
                            potentialMatch.matched++;
                        }

                        // if we are still valid and have finished, test whether we have elements after and whether these are allowed
                        if (potentialMatch) {
                            potentialMatch.finished = potentialMatch.matched === needleElements.length;
                            if (potentialMatch.finished &&
                                (!extend.allowAfter && (hackstackElementIndex + 1 < hackstackSelector.elements.length || haystackSelectorIndex + 1 < haystackSelectorPath.length))) {
                                potentialMatch = null;
                            }
                        }
                        // if null we remove, if not, we are still valid, so either push as a valid match or continue
                        if (potentialMatch) {
                            if (potentialMatch.finished) {
                                potentialMatch.length = needleElements.length;
                                potentialMatch.endPathIndex = haystackSelectorIndex;
                                potentialMatch.endPathElementIndex = hackstackElementIndex + 1; // index after end of match
                                potentialMatches.length = 0; // we don't allow matches to overlap, so start matching again
                                matches.push(potentialMatch);
                            }
                        } else {
                            potentialMatches.splice(i, 1);
                            i--;
                        }
                    }
                }
            }
            return matches;
        },
        isElementValuesEqual: function (elementValue1, elementValue2) {
            if (typeof elementValue1 === "string" || typeof elementValue2 === "string") {
                return elementValue1 === elementValue2;
            }
            if (elementValue1 instanceof tree.Attribute) {
                if (elementValue1.op !== elementValue2.op || elementValue1.key !== elementValue2.key) {
                    return false;
                }
                if (!elementValue1.value || !elementValue2.value) {
                    if (elementValue1.value || elementValue2.value) {
                        return false;
                    }
                    return true;
                }
                elementValue1 = elementValue1.value.value || elementValue1.value;
                elementValue2 = elementValue2.value.value || elementValue2.value;
                return elementValue1 === elementValue2;
            }
            elementValue1 = elementValue1.value;
            elementValue2 = elementValue2.value;
            if (elementValue1 instanceof tree.Selector) {
                if (!(elementValue2 instanceof tree.Selector) || elementValue1.elements.length !== elementValue2.elements.length) {
                    return false;
                }
                for (var i = 0; i < elementValue1.elements.length; i++) {
                    if (elementValue1.elements[i].combinator.value !== elementValue2.elements[i].combinator.value) {
                        if (i !== 0 || (elementValue1.elements[i].combinator.value || ' ') !== (elementValue2.elements[i].combinator.value || ' ')) {
                            return false;
                        }
                    }
                    if (!this.isElementValuesEqual(elementValue1.elements[i].value, elementValue2.elements[i].value)) {
                        return false;
                    }
                }
                return true;
            }
            return false;
        },
        extendSelector: function (matches, selectorPath, replacementSelector) {

            //for a set of matches, replace each match with the replacement selector

            var currentSelectorPathIndex = 0,
                currentSelectorPathElementIndex = 0,
                path = [],
                matchIndex,
                selector,
                firstElement,
                match,
                newElements;

            for (matchIndex = 0; matchIndex < matches.length; matchIndex++) {
                match = matches[matchIndex];
                selector = selectorPath[match.pathIndex];
                firstElement = new tree.Element(
                    match.initialCombinator,
                    replacementSelector.elements[0].value,
                    replacementSelector.elements[0].index,
                    replacementSelector.elements[0].currentFileInfo
                );

                if (match.pathIndex > currentSelectorPathIndex && currentSelectorPathElementIndex > 0) {
                    path[path.length - 1].elements = path[path.length - 1].elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
                    currentSelectorPathElementIndex = 0;
                    currentSelectorPathIndex++;
                }

                newElements = selector.elements
                    .slice(currentSelectorPathElementIndex, match.index)
                    .concat([firstElement])
                    .concat(replacementSelector.elements.slice(1));

                if (currentSelectorPathIndex === match.pathIndex && matchIndex > 0) {
                    path[path.length - 1].elements =
                        path[path.length - 1].elements.concat(newElements);
                } else {
                    path = path.concat(selectorPath.slice(currentSelectorPathIndex, match.pathIndex));

                    path.push(new tree.Selector(
                        newElements
                    ));
                }
                currentSelectorPathIndex = match.endPathIndex;
                currentSelectorPathElementIndex = match.endPathElementIndex;
                if (currentSelectorPathElementIndex >= selectorPath[currentSelectorPathIndex].elements.length) {
                    currentSelectorPathElementIndex = 0;
                    currentSelectorPathIndex++;
                }
            }

            if (currentSelectorPathIndex < selectorPath.length && currentSelectorPathElementIndex > 0) {
                path[path.length - 1].elements = path[path.length - 1].elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
                currentSelectorPathIndex++;
            }

            path = path.concat(selectorPath.slice(currentSelectorPathIndex, selectorPath.length));

            return path;
        },
        visitRulesetOut: function (rulesetNode) {
        },
        visitMedia: function (mediaNode, visitArgs) {
            var newAllExtends = mediaNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
            newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, mediaNode.allExtends));
            this.allExtendsStack.push(newAllExtends);
        },
        visitMediaOut: function (mediaNode) {
            this.allExtendsStack.length = this.allExtendsStack.length - 1;
        },
        visitDirective: function (directiveNode, visitArgs) {
            var newAllExtends = directiveNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
            newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, directiveNode.allExtends));
            this.allExtendsStack.push(newAllExtends);
        },
        visitDirectiveOut: function (directiveNode) {
            this.allExtendsStack.length = this.allExtendsStack.length - 1;
        }
    };

})(require('./tree'));

(function (tree) {

    tree.sourceMapOutput = function (options) {
        this._css = [];
        this._rootNode = options.rootNode;
        this._writeSourceMap = options.writeSourceMap;
        this._contentsMap = options.contentsMap;
        this._contentsIgnoredCharsMap = options.contentsIgnoredCharsMap;
        this._sourceMapFilename = options.sourceMapFilename;
        this._outputFilename = options.outputFilename;
        this._sourceMapURL = options.sourceMapURL;
        if (options.sourceMapBasepath) {
            this._sourceMapBasepath = options.sourceMapBasepath.replace(/\\/g, '/');
        }
        this._sourceMapRootpath = options.sourceMapRootpath;
        this._outputSourceFiles = options.outputSourceFiles;
        this._sourceMapGeneratorConstructor = options.sourceMapGenerator || require("source-map").SourceMapGenerator;

        if (this._sourceMapRootpath && this._sourceMapRootpath.charAt(this._sourceMapRootpath.length - 1) !== '/') {
            this._sourceMapRootpath += '/';
        }

        this._lineNumber = 0;
        this._column = 0;
    };

    tree.sourceMapOutput.prototype.normalizeFilename = function (filename) {
        filename = filename.replace(/\\/g, '/');

        if (this._sourceMapBasepath && filename.indexOf(this._sourceMapBasepath) === 0) {
            filename = filename.substring(this._sourceMapBasepath.length);
            if (filename.charAt(0) === '\\' || filename.charAt(0) === '/') {
                filename = filename.substring(1);
            }
        }
        return (this._sourceMapRootpath || "") + filename;
    };

    tree.sourceMapOutput.prototype.add = function (chunk, fileInfo, index, mapLines) {

        //ignore adding empty strings
        if (!chunk) {
            return;
        }

        var lines,
            sourceLines,
            columns,
            sourceColumns,
            i;

        if (fileInfo) {
            var inputSource = this._contentsMap[fileInfo.filename];

            // remove vars/banner added to the top of the file
            if (this._contentsIgnoredCharsMap[fileInfo.filename]) {
                // adjust the index
                index -= this._contentsIgnoredCharsMap[fileInfo.filename];
                if (index < 0) {
                    index = 0;
                }
                // adjust the source
                inputSource = inputSource.slice(this._contentsIgnoredCharsMap[fileInfo.filename]);
            }
            inputSource = inputSource.substring(0, index);
            sourceLines = inputSource.split("\n");
            sourceColumns = sourceLines[sourceLines.length - 1];
        }

        lines = chunk.split("\n");
        columns = lines[lines.length - 1];

        if (fileInfo) {
            if (!mapLines) {
                this._sourceMapGenerator.addMapping({
                    generated: {line: this._lineNumber + 1, column: this._column},
                    original: {line: sourceLines.length, column: sourceColumns.length},
                    source: this.normalizeFilename(fileInfo.filename)
                });
            } else {
                for (i = 0; i < lines.length; i++) {
                    this._sourceMapGenerator.addMapping({
                        generated: {line: this._lineNumber + i + 1, column: i === 0 ? this._column : 0},
                        original: {line: sourceLines.length + i, column: i === 0 ? sourceColumns.length : 0},
                        source: this.normalizeFilename(fileInfo.filename)
                    });
                }
            }
        }

        if (lines.length === 1) {
            this._column += columns.length;
        } else {
            this._lineNumber += lines.length - 1;
            this._column = columns.length;
        }

        this._css.push(chunk);
    };

    tree.sourceMapOutput.prototype.isEmpty = function () {
        return this._css.length === 0;
    };

    tree.sourceMapOutput.prototype.toCSS = function (env) {
        this._sourceMapGenerator = new this._sourceMapGeneratorConstructor({
            file: this._outputFilename,
            sourceRoot: null
        });

        if (this._outputSourceFiles) {
            for (var filename in this._contentsMap) {
                if (this._contentsMap.hasOwnProperty(filename)) {
                    var source = this._contentsMap[filename];
                    if (this._contentsIgnoredCharsMap[filename]) {
                        source = source.slice(this._contentsIgnoredCharsMap[filename]);
                    }
                    this._sourceMapGenerator.setSourceContent(this.normalizeFilename(filename), source);
                }
            }
        }

        this._rootNode.genCSS(env, this);

        if (this._css.length > 0) {
            var sourceMapURL,
                sourceMapContent = JSON.stringify(this._sourceMapGenerator.toJSON());

            if (this._sourceMapURL) {
                sourceMapURL = this._sourceMapURL;
            } else if (this._sourceMapFilename) {
                sourceMapURL = this.normalizeFilename(this._sourceMapFilename);
            }

            if (this._writeSourceMap) {
                this._writeSourceMap(sourceMapContent);
            } else {
                sourceMapURL = "data:application/json;base64," + require('./encoder.js').encodeBase64(sourceMapContent);
            }

            if (sourceMapURL) {
                this._css.push("/*# sourceMappingURL=" + sourceMapURL + " */");
            }
        }

        return this._css.join('');
    };

})(require('./tree'));

// wraps the source-map code in a less module
(function () {
    less.modules["source-map"] = function () {

        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */

        /**
         * Define a module along with a payload.
         * @param {string} moduleName Name for the payload
         * @param {ignored} deps Ignored. For compatibility with CommonJS AMD Spec
         * @param {function} payload Function with (require, exports, module) params
         */
        function define(moduleName, deps, payload) {
            if (typeof moduleName != "string") {
                throw new TypeError('Expected string, got: ' + moduleName);
            }

            if (arguments.length == 2) {
                payload = deps;
            }

            if (moduleName in define.modules) {
                throw new Error("Module already defined: " + moduleName);
            }
            define.modules[moduleName] = payload;
        };

        /**
         * The global store of un-instantiated modules
         */
        define.modules = {};


        /**
         * We invoke require() in the context of a Domain so we can have multiple
         * sets of modules running separate from each other.
         * This contrasts with JSMs which are singletons, Domains allows us to
         * optionally load a CommonJS module twice with separate data each time.
         * Perhaps you want 2 command lines with a different set of commands in each,
         * for example.
         */
        function Domain() {
            this.modules = {};
            this._currentModule = null;
        }

        (function () {

            /**
             * Lookup module names and resolve them by calling the definition function if
             * needed.
             * There are 2 ways to call this, either with an array of dependencies and a
             * callback to call when the dependencies are found (which can happen
             * asynchronously in an in-page context) or with a single string an no callback
             * where the dependency is resolved synchronously and returned.
             * The API is designed to be compatible with the CommonJS AMD spec and
             * RequireJS.
             * @param {string[]|string} deps A name, or names for the payload
             * @param {function|undefined} callback Function to call when the dependencies
             * are resolved
             * @return {undefined|object} The module required or undefined for
             * array/callback method
             */
            Domain.prototype.require = function (deps, callback) {
                if (Array.isArray(deps)) {
                    var params = deps.map(function (dep) {
                        return this.lookup(dep);
                    }, this);
                    if (callback) {
                        callback.apply(null, params);
                    }
                    return undefined;
                }
                else {
                    return this.lookup(deps);
                }
            };

            function normalize(path) {
                var bits = path.split('/');
                var i = 1;
                while (i < bits.length) {
                    if (bits[i] === '..') {
                        bits.splice(i - 1, 1);
                    } else if (bits[i] === '.') {
                        bits.splice(i, 1);
                    } else {
                        i++;
                    }
                }
                return bits.join('/');
            }

            function join(a, b) {
                a = a.trim();
                b = b.trim();
                if (/^\//.test(b)) {
                    return b;
                } else {
                    return a.replace(/\/*$/, '/') + b;
                }
            }

            function dirname(path) {
                var bits = path.split('/');
                bits.pop();
                return bits.join('/');
            }

            /**
             * Lookup module names and resolve them by calling the definition function if
             * needed.
             * @param {string} moduleName A name for the payload to lookup
             * @return {object} The module specified by aModuleName or null if not found.
             */
            Domain.prototype.lookup = function (moduleName) {
                if (/^\./.test(moduleName)) {
                    moduleName = normalize(join(dirname(this._currentModule), moduleName));
                }

                if (moduleName in this.modules) {
                    var module = this.modules[moduleName];
                    return module;
                }

                if (!(moduleName in define.modules)) {
                    throw new Error("Module not defined: " + moduleName);
                }

                var module = define.modules[moduleName];

                if (typeof module == "function") {
                    var exports = {};
                    var previousModule = this._currentModule;
                    this._currentModule = moduleName;
                    module(this.require.bind(this), exports, {id: moduleName, uri: ""});
                    this._currentModule = previousModule;
                    module = exports;
                }

                // cache the resulting module object for next time
                this.modules[moduleName] = module;

                return module;
            };

        }());

        define.Domain = Domain;
        define.globalDomain = new Domain();
        var require = define.globalDomain.require.bind(define.globalDomain);
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/source-map-generator', ['require', 'exports', 'module', 'source-map/base64-vlq', 'source-map/util', 'source-map/array-set'], function (require, exports, module) {

            var base64VLQ = require('./base64-vlq');
            var util = require('./util');
            var ArraySet = require('./array-set').ArraySet;

            /**
             * An instance of the SourceMapGenerator represents a source map which is
             * being built incrementally. To create a new one, you must pass an object
             * with the following properties:
             *
             *   - file: The filename of the generated source.
             *   - sourceRoot: An optional root for all URLs in this source map.
             */
            function SourceMapGenerator(aArgs) {
                this._file = util.getArg(aArgs, 'file');
                this._sourceRoot = util.getArg(aArgs, 'sourceRoot', null);
                this._sources = new ArraySet();
                this._names = new ArraySet();
                this._mappings = [];
                this._sourcesContents = null;
            }

            SourceMapGenerator.prototype._version = 3;

            /**
             * Creates a new SourceMapGenerator based on a SourceMapConsumer
             *
             * @param aSourceMapConsumer The SourceMap.
             */
            SourceMapGenerator.fromSourceMap =
                function SourceMapGenerator_fromSourceMap(aSourceMapConsumer) {
                    var sourceRoot = aSourceMapConsumer.sourceRoot;
                    var generator = new SourceMapGenerator({
                        file: aSourceMapConsumer.file,
                        sourceRoot: sourceRoot
                    });
                    aSourceMapConsumer.eachMapping(function (mapping) {
                        var newMapping = {
                            generated: {
                                line: mapping.generatedLine,
                                column: mapping.generatedColumn
                            }
                        };

                        if (mapping.source) {
                            newMapping.source = mapping.source;
                            if (sourceRoot) {
                                newMapping.source = util.relative(sourceRoot, newMapping.source);
                            }

                            newMapping.original = {
                                line: mapping.originalLine,
                                column: mapping.originalColumn
                            };

                            if (mapping.name) {
                                newMapping.name = mapping.name;
                            }
                        }

                        generator.addMapping(newMapping);
                    });
                    aSourceMapConsumer.sources.forEach(function (sourceFile) {
                        var content = aSourceMapConsumer.sourceContentFor(sourceFile);
                        if (content) {
                            generator.setSourceContent(sourceFile, content);
                        }
                    });
                    return generator;
                };

            /**
             * Add a single mapping from original source line and column to the generated
             * source's line and column for this source map being created. The mapping
             * object should have the following properties:
             *
             *   - generated: An object with the generated line and column positions.
             *   - original: An object with the original line and column positions.
             *   - source: The original source file (relative to the sourceRoot).
             *   - name: An optional original token name for this mapping.
             */
            SourceMapGenerator.prototype.addMapping =
                function SourceMapGenerator_addMapping(aArgs) {
                    var generated = util.getArg(aArgs, 'generated');
                    var original = util.getArg(aArgs, 'original', null);
                    var source = util.getArg(aArgs, 'source', null);
                    var name = util.getArg(aArgs, 'name', null);

                    this._validateMapping(generated, original, source, name);

                    if (source && !this._sources.has(source)) {
                        this._sources.add(source);
                    }

                    if (name && !this._names.has(name)) {
                        this._names.add(name);
                    }

                    this._mappings.push({
                        generatedLine: generated.line,
                        generatedColumn: generated.column,
                        originalLine: original != null && original.line,
                        originalColumn: original != null && original.column,
                        source: source,
                        name: name
                    });
                };

            /**
             * Set the source content for a source file.
             */
            SourceMapGenerator.prototype.setSourceContent =
                function SourceMapGenerator_setSourceContent(aSourceFile, aSourceContent) {
                    var source = aSourceFile;
                    if (this._sourceRoot) {
                        source = util.relative(this._sourceRoot, source);
                    }

                    if (aSourceContent !== null) {
                        // Add the source content to the _sourcesContents map.
                        // Create a new _sourcesContents map if the property is null.
                        if (!this._sourcesContents) {
                            this._sourcesContents = {};
                        }
                        this._sourcesContents[util.toSetString(source)] = aSourceContent;
                    } else {
                        // Remove the source file from the _sourcesContents map.
                        // If the _sourcesContents map is empty, set the property to null.
                        delete this._sourcesContents[util.toSetString(source)];
                        if (Object.keys(this._sourcesContents).length === 0) {
                            this._sourcesContents = null;
                        }
                    }
                };

            /**
             * Applies the mappings of a sub-source-map for a specific source file to the
             * source map being generated. Each mapping to the supplied source file is
             * rewritten using the supplied source map. Note: The resolution for the
             * resulting mappings is the minimium of this map and the supplied map.
             *
             * @param aSourceMapConsumer The source map to be applied.
             * @param aSourceFile Optional. The filename of the source file.
             *        If omitted, SourceMapConsumer's file property will be used.
             */
            SourceMapGenerator.prototype.applySourceMap =
                function SourceMapGenerator_applySourceMap(aSourceMapConsumer, aSourceFile) {
                    // If aSourceFile is omitted, we will use the file property of the SourceMap
                    if (!aSourceFile) {
                        aSourceFile = aSourceMapConsumer.file;
                    }
                    var sourceRoot = this._sourceRoot;
                    // Make "aSourceFile" relative if an absolute Url is passed.
                    if (sourceRoot) {
                        aSourceFile = util.relative(sourceRoot, aSourceFile);
                    }
                    // Applying the SourceMap can add and remove items from the sources and
                    // the names array.
                    var newSources = new ArraySet();
                    var newNames = new ArraySet();

                    // Find mappings for the "aSourceFile"
                    this._mappings.forEach(function (mapping) {
                        if (mapping.source === aSourceFile && mapping.originalLine) {
                            // Check if it can be mapped by the source map, then update the mapping.
                            var original = aSourceMapConsumer.originalPositionFor({
                                line: mapping.originalLine,
                                column: mapping.originalColumn
                            });
                            if (original.source !== null) {
                                // Copy mapping
                                if (sourceRoot) {
                                    mapping.source = util.relative(sourceRoot, original.source);
                                } else {
                                    mapping.source = original.source;
                                }
                                mapping.originalLine = original.line;
                                mapping.originalColumn = original.column;
                                if (original.name !== null && mapping.name !== null) {
                                    // Only use the identifier name if it's an identifier
                                    // in both SourceMaps
                                    mapping.name = original.name;
                                }
                            }
                        }

                        var source = mapping.source;
                        if (source && !newSources.has(source)) {
                            newSources.add(source);
                        }

                        var name = mapping.name;
                        if (name && !newNames.has(name)) {
                            newNames.add(name);
                        }

                    }, this);
                    this._sources = newSources;
                    this._names = newNames;

                    // Copy sourcesContents of applied map.
                    aSourceMapConsumer.sources.forEach(function (sourceFile) {
                        var content = aSourceMapConsumer.sourceContentFor(sourceFile);
                        if (content) {
                            if (sourceRoot) {
                                sourceFile = util.relative(sourceRoot, sourceFile);
                            }
                            this.setSourceContent(sourceFile, content);
                        }
                    }, this);
                };

            /**
             * A mapping can have one of the three levels of data:
             *
             *   1. Just the generated position.
             *   2. The Generated position, original position, and original source.
             *   3. Generated and original position, original source, as well as a name
             *      token.
             *
             * To maintain consistency, we validate that any new mapping being added falls
             * in to one of these categories.
             */
            SourceMapGenerator.prototype._validateMapping =
                function SourceMapGenerator_validateMapping(aGenerated, aOriginal, aSource,
                                                            aName) {
                    if (aGenerated && 'line' in aGenerated && 'column' in aGenerated
                        && aGenerated.line > 0 && aGenerated.column >= 0
                        && !aOriginal && !aSource && !aName) {
                        // Case 1.
                        return;
                    }
                    else if (aGenerated && 'line' in aGenerated && 'column' in aGenerated
                        && aOriginal && 'line' in aOriginal && 'column' in aOriginal
                        && aGenerated.line > 0 && aGenerated.column >= 0
                        && aOriginal.line > 0 && aOriginal.column >= 0
                        && aSource) {
                        // Cases 2 and 3.
                        return;
                    }
                    else {
                        throw new Error('Invalid mapping: ' + JSON.stringify({
                            generated: aGenerated,
                            source: aSource,
                            original: aOriginal,
                            name: aName
                        }));
                    }
                };

            /**
             * Serialize the accumulated mappings in to the stream of base 64 VLQs
             * specified by the source map format.
             */
            SourceMapGenerator.prototype._serializeMappings =
                function SourceMapGenerator_serializeMappings() {
                    var previousGeneratedColumn = 0;
                    var previousGeneratedLine = 1;
                    var previousOriginalColumn = 0;
                    var previousOriginalLine = 0;
                    var previousName = 0;
                    var previousSource = 0;
                    var result = '';
                    var mapping;

                    // The mappings must be guaranteed to be in sorted order before we start
                    // serializing them or else the generated line numbers (which are defined
                    // via the ';' separators) will be all messed up. Note: it might be more
                    // performant to maintain the sorting as we insert them, rather than as we
                    // serialize them, but the big O is the same either way.
                    this._mappings.sort(util.compareByGeneratedPositions);

                    for (var i = 0, len = this._mappings.length; i < len; i++) {
                        mapping = this._mappings[i];

                        if (mapping.generatedLine !== previousGeneratedLine) {
                            previousGeneratedColumn = 0;
                            while (mapping.generatedLine !== previousGeneratedLine) {
                                result += ';';
                                previousGeneratedLine++;
                            }
                        }
                        else {
                            if (i > 0) {
                                if (!util.compareByGeneratedPositions(mapping, this._mappings[i - 1])) {
                                    continue;
                                }
                                result += ',';
                            }
                        }

                        result += base64VLQ.encode(mapping.generatedColumn
                        - previousGeneratedColumn);
                        previousGeneratedColumn = mapping.generatedColumn;

                        if (mapping.source) {
                            result += base64VLQ.encode(this._sources.indexOf(mapping.source)
                            - previousSource);
                            previousSource = this._sources.indexOf(mapping.source);

                            // lines are stored 0-based in SourceMap spec version 3
                            result += base64VLQ.encode(mapping.originalLine - 1
                            - previousOriginalLine);
                            previousOriginalLine = mapping.originalLine - 1;

                            result += base64VLQ.encode(mapping.originalColumn
                            - previousOriginalColumn);
                            previousOriginalColumn = mapping.originalColumn;

                            if (mapping.name) {
                                result += base64VLQ.encode(this._names.indexOf(mapping.name)
                                - previousName);
                                previousName = this._names.indexOf(mapping.name);
                            }
                        }
                    }

                    return result;
                };

            SourceMapGenerator.prototype._generateSourcesContent =
                function SourceMapGenerator_generateSourcesContent(aSources, aSourceRoot) {
                    return aSources.map(function (source) {
                        if (!this._sourcesContents) {
                            return null;
                        }
                        if (aSourceRoot) {
                            source = util.relative(aSourceRoot, source);
                        }
                        var key = util.toSetString(source);
                        return Object.prototype.hasOwnProperty.call(this._sourcesContents,
                            key)
                            ? this._sourcesContents[key]
                            : null;
                    }, this);
                };

            /**
             * Externalize the source map.
             */
            SourceMapGenerator.prototype.toJSON =
                function SourceMapGenerator_toJSON() {
                    var map = {
                        version: this._version,
                        file: this._file,
                        sources: this._sources.toArray(),
                        names: this._names.toArray(),
                        mappings: this._serializeMappings()
                    };
                    if (this._sourceRoot) {
                        map.sourceRoot = this._sourceRoot;
                    }
                    if (this._sourcesContents) {
                        map.sourcesContent = this._generateSourcesContent(map.sources, map.sourceRoot);
                    }

                    return map;
                };

            /**
             * Render the source map being generated to a string.
             */
            SourceMapGenerator.prototype.toString =
                function SourceMapGenerator_toString() {
                    return JSON.stringify(this);
                };

            exports.SourceMapGenerator = SourceMapGenerator;

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         *
         * Based on the Base 64 VLQ implementation in Closure Compiler:
         * https://code.google.com/p/closure-compiler/source/browse/trunk/src/com/google/debugging/sourcemap/Base64VLQ.java
         *
         * Copyright 2011 The Closure Compiler Authors. All rights reserved.
         * Redistribution and use in source and binary forms, with or without
         * modification, are permitted provided that the following conditions are
         * met:
         *
         *  * Redistributions of source code must retain the above copyright
         *    notice, this list of conditions and the following disclaimer.
         *  * Redistributions in binary form must reproduce the above
         *    copyright notice, this list of conditions and the following
         *    disclaimer in the documentation and/or other materials provided
         *    with the distribution.
         *  * Neither the name of Google Inc. nor the names of its
         *    contributors may be used to endorse or promote products derived
         *    from this software without specific prior written permission.
         *
         * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
         * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
         * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
         * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
         * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
         * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
         * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
         * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
         * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
         * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
         * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
         */
        define('source-map/base64-vlq', ['require', 'exports', 'module', 'source-map/base64'], function (require, exports, module) {

            var base64 = require('./base64');

            // A single base 64 digit can contain 6 bits of data. For the base 64 variable
            // length quantities we use in the source map spec, the first bit is the sign,
            // the next four bits are the actual value, and the 6th bit is the
            // continuation bit. The continuation bit tells us whether there are more
            // digits in this value following this digit.
            //
            //   Continuation
            //   |    Sign
            //   |    |
            //   V    V
            //   101011

            var VLQ_BASE_SHIFT = 5;

            // binary: 100000
            var VLQ_BASE = 1 << VLQ_BASE_SHIFT;

            // binary: 011111
            var VLQ_BASE_MASK = VLQ_BASE - 1;

            // binary: 100000
            var VLQ_CONTINUATION_BIT = VLQ_BASE;

            /**
             * Converts from a two-complement value to a value where the sign bit is
             * is placed in the least significant bit.  For example, as decimals:
             *   1 becomes 2 (10 binary), -1 becomes 3 (11 binary)
             *   2 becomes 4 (100 binary), -2 becomes 5 (101 binary)
             */
            function toVLQSigned(aValue) {
                return aValue < 0
                    ? ((-aValue) << 1) + 1
                    : (aValue << 1) + 0;
            }

            /**
             * Converts to a two-complement value from a value where the sign bit is
             * is placed in the least significant bit.  For example, as decimals:
             *   2 (10 binary) becomes 1, 3 (11 binary) becomes -1
             *   4 (100 binary) becomes 2, 5 (101 binary) becomes -2
             */
            function fromVLQSigned(aValue) {
                var isNegative = (aValue & 1) === 1;
                var shifted = aValue >> 1;
                return isNegative
                    ? -shifted
                    : shifted;
            }

            /**
             * Returns the base 64 VLQ encoded value.
             */
            exports.encode = function base64VLQ_encode(aValue) {
                var encoded = "";
                var digit;

                var vlq = toVLQSigned(aValue);

                do {
                    digit = vlq & VLQ_BASE_MASK;
                    vlq >>>= VLQ_BASE_SHIFT;
                    if (vlq > 0) {
                        // There are still more digits in this value, so we must make sure the
                        // continuation bit is marked.
                        digit |= VLQ_CONTINUATION_BIT;
                    }
                    encoded += base64.encode(digit);
                } while (vlq > 0);

                return encoded;
            };

            /**
             * Decodes the next base 64 VLQ value from the given string and returns the
             * value and the rest of the string.
             */
            exports.decode = function base64VLQ_decode(aStr) {
                var i = 0;
                var strLen = aStr.length;
                var result = 0;
                var shift = 0;
                var continuation, digit;

                do {
                    if (i >= strLen) {
                        throw new Error("Expected more digits in base 64 VLQ value.");
                    }
                    digit = base64.decode(aStr.charAt(i++));
                    continuation = !!(digit & VLQ_CONTINUATION_BIT);
                    digit &= VLQ_BASE_MASK;
                    result = result + (digit << shift);
                    shift += VLQ_BASE_SHIFT;
                } while (continuation);

                return {
                    value: fromVLQSigned(result),
                    rest: aStr.slice(i)
                };
            };

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/base64', ['require', 'exports', 'module',], function (require, exports, module) {

            var charToIntMap = {};
            var intToCharMap = {};

            'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
                .split('')
                .forEach(function (ch, index) {
                    charToIntMap[ch] = index;
                    intToCharMap[index] = ch;
                });

            /**
             * Encode an integer in the range of 0 to 63 to a single base 64 digit.
             */
            exports.encode = function base64_encode(aNumber) {
                if (aNumber in intToCharMap) {
                    return intToCharMap[aNumber];
                }
                throw new TypeError("Must be between 0 and 63: " + aNumber);
            };

            /**
             * Decode a single base 64 digit to an integer.
             */
            exports.decode = function base64_decode(aChar) {
                if (aChar in charToIntMap) {
                    return charToIntMap[aChar];
                }
                throw new TypeError("Not a valid base 64 digit: " + aChar);
            };

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/util', ['require', 'exports', 'module',], function (require, exports, module) {

            /**
             * This is a helper function for getting values from parameter/options
             * objects.
             *
             * @param args The object we are extracting values from
             * @param name The name of the property we are getting.
             * @param defaultValue An optional value to return if the property is missing
             * from the object. If this is not specified and the property is missing, an
             * error will be thrown.
             */
            function getArg(aArgs, aName, aDefaultValue) {
                if (aName in aArgs) {
                    return aArgs[aName];
                } else if (arguments.length === 3) {
                    return aDefaultValue;
                } else {
                    throw new Error('"' + aName + '" is a required argument.');
                }
            }

            exports.getArg = getArg;

            var urlRegexp = /([\w+\-.]+):\/\/((\w+:\w+)@)?([\w.]+)?(:(\d+))?(\S+)?/;
            var dataUrlRegexp = /^data:.+\,.+/;

            function urlParse(aUrl) {
                var match = aUrl.match(urlRegexp);
                if (!match) {
                    return null;
                }
                return {
                    scheme: match[1],
                    auth: match[3],
                    host: match[4],
                    port: match[6],
                    path: match[7]
                };
            }

            exports.urlParse = urlParse;

            function urlGenerate(aParsedUrl) {
                var url = aParsedUrl.scheme + "://";
                if (aParsedUrl.auth) {
                    url += aParsedUrl.auth + "@"
                }
                if (aParsedUrl.host) {
                    url += aParsedUrl.host;
                }
                if (aParsedUrl.port) {
                    url += ":" + aParsedUrl.port
                }
                if (aParsedUrl.path) {
                    url += aParsedUrl.path;
                }
                return url;
            }

            exports.urlGenerate = urlGenerate;

            function join(aRoot, aPath) {
                var url;

                if (aPath.match(urlRegexp) || aPath.match(dataUrlRegexp)) {
                    return aPath;
                }

                if (aPath.charAt(0) === '/' && (url = urlParse(aRoot))) {
                    url.path = aPath;
                    return urlGenerate(url);
                }

                return aRoot.replace(/\/$/, '') + '/' + aPath;
            }

            exports.join = join;

            /**
             * Because behavior goes wacky when you set `__proto__` on objects, we
             * have to prefix all the strings in our set with an arbitrary character.
             *
             * See https://github.com/mozilla/source-map/pull/31 and
             * https://github.com/mozilla/source-map/issues/30
             *
             * @param String aStr
             */
            function toSetString(aStr) {
                return '$' + aStr;
            }

            exports.toSetString = toSetString;

            function fromSetString(aStr) {
                return aStr.substr(1);
            }

            exports.fromSetString = fromSetString;

            function relative(aRoot, aPath) {
                aRoot = aRoot.replace(/\/$/, '');

                var url = urlParse(aRoot);
                if (aPath.charAt(0) == "/" && url && url.path == "/") {
                    return aPath.slice(1);
                }

                return aPath.indexOf(aRoot + '/') === 0
                    ? aPath.substr(aRoot.length + 1)
                    : aPath;
            }

            exports.relative = relative;

            function strcmp(aStr1, aStr2) {
                var s1 = aStr1 || "";
                var s2 = aStr2 || "";
                return (s1 > s2) - (s1 < s2);
            }

            /**
             * Comparator between two mappings where the original positions are compared.
             *
             * Optionally pass in `true` as `onlyCompareGenerated` to consider two
             * mappings with the same original source/line/column, but different generated
             * line and column the same. Useful when searching for a mapping with a
             * stubbed out mapping.
             */
            function compareByOriginalPositions(mappingA, mappingB, onlyCompareOriginal) {
                var cmp;

                cmp = strcmp(mappingA.source, mappingB.source);
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.originalLine - mappingB.originalLine;
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.originalColumn - mappingB.originalColumn;
                if (cmp || onlyCompareOriginal) {
                    return cmp;
                }

                cmp = strcmp(mappingA.name, mappingB.name);
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.generatedLine - mappingB.generatedLine;
                if (cmp) {
                    return cmp;
                }

                return mappingA.generatedColumn - mappingB.generatedColumn;
            };
            exports.compareByOriginalPositions = compareByOriginalPositions;

            /**
             * Comparator between two mappings where the generated positions are
             * compared.
             *
             * Optionally pass in `true` as `onlyCompareGenerated` to consider two
             * mappings with the same generated line and column, but different
             * source/name/original line and column the same. Useful when searching for a
             * mapping with a stubbed out mapping.
             */
            function compareByGeneratedPositions(mappingA, mappingB, onlyCompareGenerated) {
                var cmp;

                cmp = mappingA.generatedLine - mappingB.generatedLine;
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.generatedColumn - mappingB.generatedColumn;
                if (cmp || onlyCompareGenerated) {
                    return cmp;
                }

                cmp = strcmp(mappingA.source, mappingB.source);
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.originalLine - mappingB.originalLine;
                if (cmp) {
                    return cmp;
                }

                cmp = mappingA.originalColumn - mappingB.originalColumn;
                if (cmp) {
                    return cmp;
                }

                return strcmp(mappingA.name, mappingB.name);
            };
            exports.compareByGeneratedPositions = compareByGeneratedPositions;

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/array-set', ['require', 'exports', 'module', 'source-map/util'], function (require, exports, module) {

            var util = require('./util');

            /**
             * A data structure which is a combination of an array and a set. Adding a new
             * member is O(1), testing for membership is O(1), and finding the index of an
             * element is O(1). Removing elements from the set is not supported. Only
             * strings are supported for membership.
             */
            function ArraySet() {
                this._array = [];
                this._set = {};
            }

            /**
             * Static method for creating ArraySet instances from an existing array.
             */
            ArraySet.fromArray = function ArraySet_fromArray(aArray, aAllowDuplicates) {
                var set = new ArraySet();
                for (var i = 0, len = aArray.length; i < len; i++) {
                    set.add(aArray[i], aAllowDuplicates);
                }
                return set;
            };

            /**
             * Add the given string to this set.
             *
             * @param String aStr
             */
            ArraySet.prototype.add = function ArraySet_add(aStr, aAllowDuplicates) {
                var isDuplicate = this.has(aStr);
                var idx = this._array.length;
                if (!isDuplicate || aAllowDuplicates) {
                    this._array.push(aStr);
                }
                if (!isDuplicate) {
                    this._set[util.toSetString(aStr)] = idx;
                }
            };

            /**
             * Is the given string a member of this set?
             *
             * @param String aStr
             */
            ArraySet.prototype.has = function ArraySet_has(aStr) {
                return Object.prototype.hasOwnProperty.call(this._set,
                    util.toSetString(aStr));
            };

            /**
             * What is the index of the given string in the array?
             *
             * @param String aStr
             */
            ArraySet.prototype.indexOf = function ArraySet_indexOf(aStr) {
                if (this.has(aStr)) {
                    return this._set[util.toSetString(aStr)];
                }
                throw new Error('"' + aStr + '" is not in the set.');
            };

            /**
             * What is the element at the given index?
             *
             * @param Number aIdx
             */
            ArraySet.prototype.at = function ArraySet_at(aIdx) {
                if (aIdx >= 0 && aIdx < this._array.length) {
                    return this._array[aIdx];
                }
                throw new Error('No element indexed by ' + aIdx);
            };

            /**
             * Returns the array representation of this set (which has the proper indices
             * indicated by indexOf). Note that this is a copy of the internal array used
             * for storing the members so that no one can mess with internal state.
             */
            ArraySet.prototype.toArray = function ArraySet_toArray() {
                return this._array.slice();
            };

            exports.ArraySet = ArraySet;

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/source-map-consumer', ['require', 'exports', 'module', 'source-map/util', 'source-map/binary-search', 'source-map/array-set', 'source-map/base64-vlq'], function (require, exports, module) {

            var util = require('./util');
            var binarySearch = require('./binary-search');
            var ArraySet = require('./array-set').ArraySet;
            var base64VLQ = require('./base64-vlq');

            /**
             * A SourceMapConsumer instance represents a parsed source map which we can
             * query for information about the original file positions by giving it a file
             * position in the generated source.
             *
             * The only parameter is the raw source map (either as a JSON string, or
             * already parsed to an object). According to the spec, source maps have the
             * following attributes:
             *
             *   - version: Which version of the source map spec this map is following.
             *   - sources: An array of URLs to the original source files.
             *   - names: An array of identifiers which can be referrenced by individual mappings.
             *   - sourceRoot: Optional. The URL root from which all sources are relative.
             *   - sourcesContent: Optional. An array of contents of the original source files.
             *   - mappings: A string of base64 VLQs which contain the actual mappings.
             *   - file: The generated file this source map is associated with.
             *
             * Here is an example source map, taken from the source map spec[0]:
             *
             *     {
   *       version : 3,
   *       file: "out.js",
   *       sourceRoot : "",
   *       sources: ["foo.js", "bar.js"],
   *       names: ["src", "maps", "are", "fun"],
   *       mappings: "AA,AB;;ABCDE;"
   *     }
             *
             * [0]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit?pli=1#
             */
            function SourceMapConsumer(aSourceMap) {
                var sourceMap = aSourceMap;
                if (typeof aSourceMap === 'string') {
                    sourceMap = JSON.parse(aSourceMap.replace(/^\)\]\}'/, ''));
                }

                var version = util.getArg(sourceMap, 'version');
                var sources = util.getArg(sourceMap, 'sources');
                // Sass 3.3 leaves out the 'names' array, so we deviate from the spec (which
                // requires the array) to play nice here.
                var names = util.getArg(sourceMap, 'names', []);
                var sourceRoot = util.getArg(sourceMap, 'sourceRoot', null);
                var sourcesContent = util.getArg(sourceMap, 'sourcesContent', null);
                var mappings = util.getArg(sourceMap, 'mappings');
                var file = util.getArg(sourceMap, 'file', null);

                // Once again, Sass deviates from the spec and supplies the version as a
                // string rather than a number, so we use loose equality checking here.
                if (version != this._version) {
                    throw new Error('Unsupported version: ' + version);
                }

                // Pass `true` below to allow duplicate names and sources. While source maps
                // are intended to be compressed and deduplicated, the TypeScript compiler
                // sometimes generates source maps with duplicates in them. See Github issue
                // #72 and bugzil.la/889492.
                this._names = ArraySet.fromArray(names, true);
                this._sources = ArraySet.fromArray(sources, true);

                this.sourceRoot = sourceRoot;
                this.sourcesContent = sourcesContent;
                this._mappings = mappings;
                this.file = file;
            }

            /**
             * Create a SourceMapConsumer from a SourceMapGenerator.
             *
             * @param SourceMapGenerator aSourceMap
             *        The source map that will be consumed.
             * @returns SourceMapConsumer
             */
            SourceMapConsumer.fromSourceMap =
                function SourceMapConsumer_fromSourceMap(aSourceMap) {
                    var smc = Object.create(SourceMapConsumer.prototype);

                    smc._names = ArraySet.fromArray(aSourceMap._names.toArray(), true);
                    smc._sources = ArraySet.fromArray(aSourceMap._sources.toArray(), true);
                    smc.sourceRoot = aSourceMap._sourceRoot;
                    smc.sourcesContent = aSourceMap._generateSourcesContent(smc._sources.toArray(),
                        smc.sourceRoot);
                    smc.file = aSourceMap._file;

                    smc.__generatedMappings = aSourceMap._mappings.slice()
                        .sort(util.compareByGeneratedPositions);
                    smc.__originalMappings = aSourceMap._mappings.slice()
                        .sort(util.compareByOriginalPositions);

                    return smc;
                };

            /**
             * The version of the source mapping spec that we are consuming.
             */
            SourceMapConsumer.prototype._version = 3;

            /**
             * The list of original sources.
             */
            Object.defineProperty(SourceMapConsumer.prototype, 'sources', {
                get: function () {
                    return this._sources.toArray().map(function (s) {
                        return this.sourceRoot ? util.join(this.sourceRoot, s) : s;
                    }, this);
                }
            });

            // `__generatedMappings` and `__originalMappings` are arrays that hold the
            // parsed mapping coordinates from the source map's "mappings" attribute. They
            // are lazily instantiated, accessed via the `_generatedMappings` and
            // `_originalMappings` getters respectively, and we only parse the mappings
            // and create these arrays once queried for a source location. We jump through
            // these hoops because there can be many thousands of mappings, and parsing
            // them is expensive, so we only want to do it if we must.
            //
            // Each object in the arrays is of the form:
            //
            //     {
            //       generatedLine: The line number in the generated code,
            //       generatedColumn: The column number in the generated code,
            //       source: The path to the original source file that generated this
            //               chunk of code,
            //       originalLine: The line number in the original source that
            //                     corresponds to this chunk of generated code,
            //       originalColumn: The column number in the original source that
            //                       corresponds to this chunk of generated code,
            //       name: The name of the original symbol which generated this chunk of
            //             code.
            //     }
            //
            // All properties except for `generatedLine` and `generatedColumn` can be
            // `null`.
            //
            // `_generatedMappings` is ordered by the generated positions.
            //
            // `_originalMappings` is ordered by the original positions.

            SourceMapConsumer.prototype.__generatedMappings = null;
            Object.defineProperty(SourceMapConsumer.prototype, '_generatedMappings', {
                get: function () {
                    if (!this.__generatedMappings) {
                        this.__generatedMappings = [];
                        this.__originalMappings = [];
                        this._parseMappings(this._mappings, this.sourceRoot);
                    }

                    return this.__generatedMappings;
                }
            });

            SourceMapConsumer.prototype.__originalMappings = null;
            Object.defineProperty(SourceMapConsumer.prototype, '_originalMappings', {
                get: function () {
                    if (!this.__originalMappings) {
                        this.__generatedMappings = [];
                        this.__originalMappings = [];
                        this._parseMappings(this._mappings, this.sourceRoot);
                    }

                    return this.__originalMappings;
                }
            });

            /**
             * Parse the mappings in a string in to a data structure which we can easily
             * query (the ordered arrays in the `this.__generatedMappings` and
             * `this.__originalMappings` properties).
             */
            SourceMapConsumer.prototype._parseMappings =
                function SourceMapConsumer_parseMappings(aStr, aSourceRoot) {
                    var generatedLine = 1;
                    var previousGeneratedColumn = 0;
                    var previousOriginalLine = 0;
                    var previousOriginalColumn = 0;
                    var previousSource = 0;
                    var previousName = 0;
                    var mappingSeparator = /^[,;]/;
                    var str = aStr;
                    var mapping;
                    var temp;

                    while (str.length > 0) {
                        if (str.charAt(0) === ';') {
                            generatedLine++;
                            str = str.slice(1);
                            previousGeneratedColumn = 0;
                        }
                        else if (str.charAt(0) === ',') {
                            str = str.slice(1);
                        }
                        else {
                            mapping = {};
                            mapping.generatedLine = generatedLine;

                            // Generated column.
                            temp = base64VLQ.decode(str);
                            mapping.generatedColumn = previousGeneratedColumn + temp.value;
                            previousGeneratedColumn = mapping.generatedColumn;
                            str = temp.rest;

                            if (str.length > 0 && !mappingSeparator.test(str.charAt(0))) {
                                // Original source.
                                temp = base64VLQ.decode(str);
                                mapping.source = this._sources.at(previousSource + temp.value);
                                previousSource += temp.value;
                                str = temp.rest;
                                if (str.length === 0 || mappingSeparator.test(str.charAt(0))) {
                                    throw new Error('Found a source, but no line and column');
                                }

                                // Original line.
                                temp = base64VLQ.decode(str);
                                mapping.originalLine = previousOriginalLine + temp.value;
                                previousOriginalLine = mapping.originalLine;
                                // Lines are stored 0-based
                                mapping.originalLine += 1;
                                str = temp.rest;
                                if (str.length === 0 || mappingSeparator.test(str.charAt(0))) {
                                    throw new Error('Found a source and line, but no column');
                                }

                                // Original column.
                                temp = base64VLQ.decode(str);
                                mapping.originalColumn = previousOriginalColumn + temp.value;
                                previousOriginalColumn = mapping.originalColumn;
                                str = temp.rest;

                                if (str.length > 0 && !mappingSeparator.test(str.charAt(0))) {
                                    // Original name.
                                    temp = base64VLQ.decode(str);
                                    mapping.name = this._names.at(previousName + temp.value);
                                    previousName += temp.value;
                                    str = temp.rest;
                                }
                            }

                            this.__generatedMappings.push(mapping);
                            if (typeof mapping.originalLine === 'number') {
                                this.__originalMappings.push(mapping);
                            }
                        }
                    }

                    this.__originalMappings.sort(util.compareByOriginalPositions);
                };

            /**
             * Find the mapping that best matches the hypothetical "needle" mapping that
             * we are searching for in the given "haystack" of mappings.
             */
            SourceMapConsumer.prototype._findMapping =
                function SourceMapConsumer_findMapping(aNeedle, aMappings, aLineName,
                                                       aColumnName, aComparator) {
                    // To return the position we are searching for, we must first find the
                    // mapping for the given position and then return the opposite position it
                    // points to. Because the mappings are sorted, we can use binary search to
                    // find the best mapping.

                    if (aNeedle[aLineName] <= 0) {
                        throw new TypeError('Line must be greater than or equal to 1, got '
                        + aNeedle[aLineName]);
                    }
                    if (aNeedle[aColumnName] < 0) {
                        throw new TypeError('Column must be greater than or equal to 0, got '
                        + aNeedle[aColumnName]);
                    }

                    return binarySearch.search(aNeedle, aMappings, aComparator);
                };

            /**
             * Returns the original source, line, and column information for the generated
             * source's line and column positions provided. The only argument is an object
             * with the following properties:
             *
             *   - line: The line number in the generated source.
             *   - column: The column number in the generated source.
             *
             * and an object is returned with the following properties:
             *
             *   - source: The original source file, or null.
             *   - line: The line number in the original source, or null.
             *   - column: The column number in the original source, or null.
             *   - name: The original identifier, or null.
             */
            SourceMapConsumer.prototype.originalPositionFor =
                function SourceMapConsumer_originalPositionFor(aArgs) {
                    var needle = {
                        generatedLine: util.getArg(aArgs, 'line'),
                        generatedColumn: util.getArg(aArgs, 'column')
                    };

                    var mapping = this._findMapping(needle,
                        this._generatedMappings,
                        "generatedLine",
                        "generatedColumn",
                        util.compareByGeneratedPositions);

                    if (mapping) {
                        var source = util.getArg(mapping, 'source', null);
                        if (source && this.sourceRoot) {
                            source = util.join(this.sourceRoot, source);
                        }
                        return {
                            source: source,
                            line: util.getArg(mapping, 'originalLine', null),
                            column: util.getArg(mapping, 'originalColumn', null),
                            name: util.getArg(mapping, 'name', null)
                        };
                    }

                    return {
                        source: null,
                        line: null,
                        column: null,
                        name: null
                    };
                };

            /**
             * Returns the original source content. The only argument is the url of the
             * original source file. Returns null if no original source content is
             * availible.
             */
            SourceMapConsumer.prototype.sourceContentFor =
                function SourceMapConsumer_sourceContentFor(aSource) {
                    if (!this.sourcesContent) {
                        return null;
                    }

                    if (this.sourceRoot) {
                        aSource = util.relative(this.sourceRoot, aSource);
                    }

                    if (this._sources.has(aSource)) {
                        return this.sourcesContent[this._sources.indexOf(aSource)];
                    }

                    var url;
                    if (this.sourceRoot
                        && (url = util.urlParse(this.sourceRoot))) {
                        // XXX: file:// URIs and absolute paths lead to unexpected behavior for
                        // many users. We can help them out when they expect file:// URIs to
                        // behave like it would if they were running a local HTTP server. See
                        // https://bugzilla.mozilla.org/show_bug.cgi?id=885597.
                        var fileUriAbsPath = aSource.replace(/^file:\/\//, "");
                        if (url.scheme == "file"
                            && this._sources.has(fileUriAbsPath)) {
                            return this.sourcesContent[this._sources.indexOf(fileUriAbsPath)]
                        }

                        if ((!url.path || url.path == "/")
                            && this._sources.has("/" + aSource)) {
                            return this.sourcesContent[this._sources.indexOf("/" + aSource)];
                        }
                    }

                    throw new Error('"' + aSource + '" is not in the SourceMap.');
                };

            /**
             * Returns the generated line and column information for the original source,
             * line, and column positions provided. The only argument is an object with
             * the following properties:
             *
             *   - source: The filename of the original source.
             *   - line: The line number in the original source.
             *   - column: The column number in the original source.
             *
             * and an object is returned with the following properties:
             *
             *   - line: The line number in the generated source, or null.
             *   - column: The column number in the generated source, or null.
             */
            SourceMapConsumer.prototype.generatedPositionFor =
                function SourceMapConsumer_generatedPositionFor(aArgs) {
                    var needle = {
                        source: util.getArg(aArgs, 'source'),
                        originalLine: util.getArg(aArgs, 'line'),
                        originalColumn: util.getArg(aArgs, 'column')
                    };

                    if (this.sourceRoot) {
                        needle.source = util.relative(this.sourceRoot, needle.source);
                    }

                    var mapping = this._findMapping(needle,
                        this._originalMappings,
                        "originalLine",
                        "originalColumn",
                        util.compareByOriginalPositions);

                    if (mapping) {
                        return {
                            line: util.getArg(mapping, 'generatedLine', null),
                            column: util.getArg(mapping, 'generatedColumn', null)
                        };
                    }

                    return {
                        line: null,
                        column: null
                    };
                };

            SourceMapConsumer.GENERATED_ORDER = 1;
            SourceMapConsumer.ORIGINAL_ORDER = 2;

            /**
             * Iterate over each mapping between an original source/line/column and a
             * generated line/column in this source map.
             *
             * @param Function aCallback
             *        The function that is called with each mapping.
             * @param Object aContext
             *        Optional. If specified, this object will be the value of `this` every
             *        time that `aCallback` is called.
             * @param aOrder
             *        Either `SourceMapConsumer.GENERATED_ORDER` or
             *        `SourceMapConsumer.ORIGINAL_ORDER`. Specifies whether you want to
             *        iterate over the mappings sorted by the generated file's line/column
             *        order or the original's source/line/column order, respectively. Defaults to
             *        `SourceMapConsumer.GENERATED_ORDER`.
             */
            SourceMapConsumer.prototype.eachMapping =
                function SourceMapConsumer_eachMapping(aCallback, aContext, aOrder) {
                    var context = aContext || null;
                    var order = aOrder || SourceMapConsumer.GENERATED_ORDER;

                    var mappings;
                    switch (order) {
                        case SourceMapConsumer.GENERATED_ORDER:
                            mappings = this._generatedMappings;
                            break;
                        case SourceMapConsumer.ORIGINAL_ORDER:
                            mappings = this._originalMappings;
                            break;
                        default:
                            throw new Error("Unknown order of iteration.");
                    }

                    var sourceRoot = this.sourceRoot;
                    mappings.map(function (mapping) {
                        var source = mapping.source;
                        if (source && sourceRoot) {
                            source = util.join(sourceRoot, source);
                        }
                        return {
                            source: source,
                            generatedLine: mapping.generatedLine,
                            generatedColumn: mapping.generatedColumn,
                            originalLine: mapping.originalLine,
                            originalColumn: mapping.originalColumn,
                            name: mapping.name
                        };
                    }).forEach(aCallback, context);
                };

            exports.SourceMapConsumer = SourceMapConsumer;

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/binary-search', ['require', 'exports', 'module',], function (require, exports, module) {

            /**
             * Recursive implementation of binary search.
             *
             * @param aLow Indices here and lower do not contain the needle.
             * @param aHigh Indices here and higher do not contain the needle.
             * @param aNeedle The element being searched for.
             * @param aHaystack The non-empty array being searched.
             * @param aCompare Function which takes two elements and returns -1, 0, or 1.
             */
            function recursiveSearch(aLow, aHigh, aNeedle, aHaystack, aCompare) {
                // This function terminates when one of the following is true:
                //
                //   1. We find the exact element we are looking for.
                //
                //   2. We did not find the exact element, but we can return the next
                //      closest element that is less than that element.
                //
                //   3. We did not find the exact element, and there is no next-closest
                //      element which is less than the one we are searching for, so we
                //      return null.
                var mid = Math.floor((aHigh - aLow) / 2) + aLow;
                var cmp = aCompare(aNeedle, aHaystack[mid], true);
                if (cmp === 0) {
                    // Found the element we are looking for.
                    return aHaystack[mid];
                }
                else if (cmp > 0) {
                    // aHaystack[mid] is greater than our needle.
                    if (aHigh - mid > 1) {
                        // The element is in the upper half.
                        return recursiveSearch(mid, aHigh, aNeedle, aHaystack, aCompare);
                    }
                    // We did not find an exact match, return the next closest one
                    // (termination case 2).
                    return aHaystack[mid];
                }
                else {
                    // aHaystack[mid] is less than our needle.
                    if (mid - aLow > 1) {
                        // The element is in the lower half.
                        return recursiveSearch(aLow, mid, aNeedle, aHaystack, aCompare);
                    }
                    // The exact needle element was not found in this haystack. Determine if
                    // we are in termination case (2) or (3) and return the appropriate thing.
                    return aLow < 0
                        ? null
                        : aHaystack[aLow];
                }
            }

            /**
             * This is an implementation of binary search which will always try and return
             * the next lowest value checked if there is no exact hit. This is because
             * mappings between original and generated line/col pairs are single points,
             * and there is an implicit region between each of them, so a miss just means
             * that you aren't on the very start of a region.
             *
             * @param aNeedle The element you are looking for.
             * @param aHaystack The array that is being searched.
             * @param aCompare A function which takes the needle and an element in the
             *     array and returns -1, 0, or 1 depending on whether the needle is less
             *     than, equal to, or greater than the element, respectively.
             */
            exports.search = function search(aNeedle, aHaystack, aCompare) {
                return aHaystack.length > 0
                    ? recursiveSearch(-1, aHaystack.length, aNeedle, aHaystack, aCompare)
                    : null;
            };

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
        /*
         * Copyright 2011 Mozilla Foundation and contributors
         * Licensed under the New BSD license. See LICENSE or:
         * http://opensource.org/licenses/BSD-3-Clause
         */
        define('source-map/source-node', ['require', 'exports', 'module', 'source-map/source-map-generator', 'source-map/util'], function (require, exports, module) {

            var SourceMapGenerator = require('./source-map-generator').SourceMapGenerator;
            var util = require('./util');

            /**
             * SourceNodes provide a way to abstract over interpolating/concatenating
             * snippets of generated JavaScript source code while maintaining the line and
             * column information associated with the original source code.
             *
             * @param aLine The original line number.
             * @param aColumn The original column number.
             * @param aSource The original source's filename.
             * @param aChunks Optional. An array of strings which are snippets of
             *        generated JS, or other SourceNodes.
             * @param aName The original identifier.
             */
            function SourceNode(aLine, aColumn, aSource, aChunks, aName) {
                this.children = [];
                this.sourceContents = {};
                this.line = aLine === undefined ? null : aLine;
                this.column = aColumn === undefined ? null : aColumn;
                this.source = aSource === undefined ? null : aSource;
                this.name = aName === undefined ? null : aName;
                if (aChunks != null) this.add(aChunks);
            }

            /**
             * Creates a SourceNode from generated code and a SourceMapConsumer.
             *
             * @param aGeneratedCode The generated code
             * @param aSourceMapConsumer The SourceMap for the generated code
             */
            SourceNode.fromStringWithSourceMap =
                function SourceNode_fromStringWithSourceMap(aGeneratedCode, aSourceMapConsumer) {
                    // The SourceNode we want to fill with the generated code
                    // and the SourceMap
                    var node = new SourceNode();

                    // The generated code
                    // Processed fragments are removed from this array.
                    var remainingLines = aGeneratedCode.split('\n');

                    // We need to remember the position of "remainingLines"
                    var lastGeneratedLine = 1, lastGeneratedColumn = 0;

                    // The generate SourceNodes we need a code range.
                    // To extract it current and last mapping is used.
                    // Here we store the last mapping.
                    var lastMapping = null;

                    aSourceMapConsumer.eachMapping(function (mapping) {
                        if (lastMapping === null) {
                            // We add the generated code until the first mapping
                            // to the SourceNode without any mapping.
                            // Each line is added as separate string.
                            while (lastGeneratedLine < mapping.generatedLine) {
                                node.add(remainingLines.shift() + "\n");
                                lastGeneratedLine++;
                            }
                            if (lastGeneratedColumn < mapping.generatedColumn) {
                                var nextLine = remainingLines[0];
                                node.add(nextLine.substr(0, mapping.generatedColumn));
                                remainingLines[0] = nextLine.substr(mapping.generatedColumn);
                                lastGeneratedColumn = mapping.generatedColumn;
                            }
                        } else {
                            // We add the code from "lastMapping" to "mapping":
                            // First check if there is a new line in between.
                            if (lastGeneratedLine < mapping.generatedLine) {
                                var code = "";
                                // Associate full lines with "lastMapping"
                                do {
                                    code += remainingLines.shift() + "\n";
                                    lastGeneratedLine++;
                                    lastGeneratedColumn = 0;
                                } while (lastGeneratedLine < mapping.generatedLine);
                                // When we reached the correct line, we add code until we
                                // reach the correct column too.
                                if (lastGeneratedColumn < mapping.generatedColumn) {
                                    var nextLine = remainingLines[0];
                                    code += nextLine.substr(0, mapping.generatedColumn);
                                    remainingLines[0] = nextLine.substr(mapping.generatedColumn);
                                    lastGeneratedColumn = mapping.generatedColumn;
                                }
                                // Create the SourceNode.
                                addMappingWithCode(lastMapping, code);
                            } else {
                                // There is no new line in between.
                                // Associate the code between "lastGeneratedColumn" and
                                // "mapping.generatedColumn" with "lastMapping"
                                var nextLine = remainingLines[0];
                                var code = nextLine.substr(0, mapping.generatedColumn -
                                lastGeneratedColumn);
                                remainingLines[0] = nextLine.substr(mapping.generatedColumn -
                                lastGeneratedColumn);
                                lastGeneratedColumn = mapping.generatedColumn;
                                addMappingWithCode(lastMapping, code);
                            }
                        }
                        lastMapping = mapping;
                    }, this);
                    // We have processed all mappings.
                    // Associate the remaining code in the current line with "lastMapping"
                    // and add the remaining lines without any mapping
                    addMappingWithCode(lastMapping, remainingLines.join("\n"));

                    // Copy sourcesContent into SourceNode
                    aSourceMapConsumer.sources.forEach(function (sourceFile) {
                        var content = aSourceMapConsumer.sourceContentFor(sourceFile);
                        if (content) {
                            node.setSourceContent(sourceFile, content);
                        }
                    });

                    return node;

                    function addMappingWithCode(mapping, code) {
                        if (mapping === null || mapping.source === undefined) {
                            node.add(code);
                        } else {
                            node.add(new SourceNode(mapping.originalLine,
                                mapping.originalColumn,
                                mapping.source,
                                code,
                                mapping.name));
                        }
                    }
                };

            /**
             * Add a chunk of generated JS to this source node.
             *
             * @param aChunk A string snippet of generated JS code, another instance of
             *        SourceNode, or an array where each member is one of those things.
             */
            SourceNode.prototype.add = function SourceNode_add(aChunk) {
                if (Array.isArray(aChunk)) {
                    aChunk.forEach(function (chunk) {
                        this.add(chunk);
                    }, this);
                }
                else if (aChunk instanceof SourceNode || typeof aChunk === "string") {
                    if (aChunk) {
                        this.children.push(aChunk);
                    }
                }
                else {
                    throw new TypeError(
                        "Expected a SourceNode, string, or an array of SourceNodes and strings. Got " + aChunk
                    );
                }
                return this;
            };

            /**
             * Add a chunk of generated JS to the beginning of this source node.
             *
             * @param aChunk A string snippet of generated JS code, another instance of
             *        SourceNode, or an array where each member is one of those things.
             */
            SourceNode.prototype.prepend = function SourceNode_prepend(aChunk) {
                if (Array.isArray(aChunk)) {
                    for (var i = aChunk.length - 1; i >= 0; i--) {
                        this.prepend(aChunk[i]);
                    }
                }
                else if (aChunk instanceof SourceNode || typeof aChunk === "string") {
                    this.children.unshift(aChunk);
                }
                else {
                    throw new TypeError(
                        "Expected a SourceNode, string, or an array of SourceNodes and strings. Got " + aChunk
                    );
                }
                return this;
            };

            /**
             * Walk over the tree of JS snippets in this node and its children. The
             * walking function is called once for each snippet of JS and is passed that
             * snippet and the its original associated source's line/column location.
             *
             * @param aFn The traversal function.
             */
            SourceNode.prototype.walk = function SourceNode_walk(aFn) {
                var chunk;
                for (var i = 0, len = this.children.length; i < len; i++) {
                    chunk = this.children[i];
                    if (chunk instanceof SourceNode) {
                        chunk.walk(aFn);
                    }
                    else {
                        if (chunk !== '') {
                            aFn(chunk, {
                                source: this.source,
                                line: this.line,
                                column: this.column,
                                name: this.name
                            });
                        }
                    }
                }
            };

            /**
             * Like `String.prototype.join` except for SourceNodes. Inserts `aStr` between
             * each of `this.children`.
             *
             * @param aSep The separator.
             */
            SourceNode.prototype.join = function SourceNode_join(aSep) {
                var newChildren;
                var i;
                var len = this.children.length;
                if (len > 0) {
                    newChildren = [];
                    for (i = 0; i < len - 1; i++) {
                        newChildren.push(this.children[i]);
                        newChildren.push(aSep);
                    }
                    newChildren.push(this.children[i]);
                    this.children = newChildren;
                }
                return this;
            };

            /**
             * Call String.prototype.replace on the very right-most source snippet. Useful
             * for trimming whitespace from the end of a source node, etc.
             *
             * @param aPattern The pattern to replace.
             * @param aReplacement The thing to replace the pattern with.
             */
            SourceNode.prototype.replaceRight = function SourceNode_replaceRight(aPattern, aReplacement) {
                var lastChild = this.children[this.children.length - 1];
                if (lastChild instanceof SourceNode) {
                    lastChild.replaceRight(aPattern, aReplacement);
                }
                else if (typeof lastChild === 'string') {
                    this.children[this.children.length - 1] = lastChild.replace(aPattern, aReplacement);
                }
                else {
                    this.children.push(''.replace(aPattern, aReplacement));
                }
                return this;
            };

            /**
             * Set the source content for a source file. This will be added to the SourceMapGenerator
             * in the sourcesContent field.
             *
             * @param aSourceFile The filename of the source file
             * @param aSourceContent The content of the source file
             */
            SourceNode.prototype.setSourceContent =
                function SourceNode_setSourceContent(aSourceFile, aSourceContent) {
                    this.sourceContents[util.toSetString(aSourceFile)] = aSourceContent;
                };

            /**
             * Walk over the tree of SourceNodes. The walking function is called for each
             * source file content and is passed the filename and source content.
             *
             * @param aFn The traversal function.
             */
            SourceNode.prototype.walkSourceContents =
                function SourceNode_walkSourceContents(aFn) {
                    for (var i = 0, len = this.children.length; i < len; i++) {
                        if (this.children[i] instanceof SourceNode) {
                            this.children[i].walkSourceContents(aFn);
                        }
                    }

                    var sources = Object.keys(this.sourceContents);
                    for (var i = 0, len = sources.length; i < len; i++) {
                        aFn(util.fromSetString(sources[i]), this.sourceContents[sources[i]]);
                    }
                };

            /**
             * Return the string representation of this source node. Walks over the tree
             * and concatenates all the various snippets together to one string.
             */
            SourceNode.prototype.toString = function SourceNode_toString() {
                var str = "";
                this.walk(function (chunk) {
                    str += chunk;
                });
                return str;
            };

            /**
             * Returns the string representation of this source node along with a source
             * map.
             */
            SourceNode.prototype.toStringWithSourceMap = function SourceNode_toStringWithSourceMap(aArgs) {
                var generated = {
                    code: "",
                    line: 1,
                    column: 0
                };
                var map = new SourceMapGenerator(aArgs);
                var sourceMappingActive = false;
                var lastOriginalSource = null;
                var lastOriginalLine = null;
                var lastOriginalColumn = null;
                var lastOriginalName = null;
                this.walk(function (chunk, original) {
                    generated.code += chunk;
                    if (original.source !== null
                        && original.line !== null
                        && original.column !== null) {
                        if (lastOriginalSource !== original.source
                            || lastOriginalLine !== original.line
                            || lastOriginalColumn !== original.column
                            || lastOriginalName !== original.name) {
                            map.addMapping({
                                source: original.source,
                                original: {
                                    line: original.line,
                                    column: original.column
                                },
                                generated: {
                                    line: generated.line,
                                    column: generated.column
                                },
                                name: original.name
                            });
                        }
                        lastOriginalSource = original.source;
                        lastOriginalLine = original.line;
                        lastOriginalColumn = original.column;
                        lastOriginalName = original.name;
                        sourceMappingActive = true;
                    } else if (sourceMappingActive) {
                        map.addMapping({
                            generated: {
                                line: generated.line,
                                column: generated.column
                            }
                        });
                        lastOriginalSource = null;
                        sourceMappingActive = false;
                    }
                    chunk.split('').forEach(function (ch) {
                        if (ch === '\n') {
                            generated.line++;
                            generated.column = 0;
                        } else {
                            generated.column++;
                        }
                    });
                });
                this.walkSourceContents(function (sourceFile, sourceContent) {
                    map.setSourceContent(sourceFile, sourceContent);
                });

                return {code: generated.code, map: map};
            };

            exports.SourceNode = SourceNode;

        });
        /* -*- Mode: js; js-indent-level: 2; -*- */
///////////////////////////////////////////////////////////////////////////////

        this.sourceMap = {
            SourceMapConsumer: require('source-map/source-map-consumer').SourceMapConsumer,
            SourceMapGenerator: require('source-map/source-map-generator').SourceMapGenerator,
            SourceNode: require('source-map/source-node').SourceNode
        };

// footer to wrap "source-map" module
        return this.sourceMap;
    }();
})();


/* Less.js v1.7.5 RHINO | Copyright (c) 2009-2014, Alexis Sellier <self@cloudhead.net> */

/*global name:true, less, loadStyleSheet, os */

function formatError(ctx, options) {
    options = options || {};

    var message = "";
    var extract = ctx.extract;
    var error = [];

//    var stylize = options.color ? require('./lessc_helper').stylize : function (str) { return str; };
    var stylize = function (str) {
        return str;
    };

    // only output a stack if it isn't a less error
    if (ctx.stack && !ctx.type) {
        return stylize(ctx.stack, 'red');
    }

    if (!ctx.hasOwnProperty('index') || !extract) {
        return ctx.stack || ctx.message;
    }

    if (typeof(extract[0]) === 'string') {
        error.push(stylize((ctx.line - 1) + ' ' + extract[0], 'grey'));
    }

    if (typeof(extract[1]) === 'string') {
        var errorTxt = ctx.line + ' ';
        if (extract[1]) {
            errorTxt += extract[1].slice(0, ctx.column) +
            stylize(stylize(stylize(extract[1][ctx.column], 'bold') +
            extract[1].slice(ctx.column + 1), 'red'), 'inverse');
        }
        error.push(errorTxt);
    }

    if (typeof(extract[2]) === 'string') {
        error.push(stylize((ctx.line + 1) + ' ' + extract[2], 'grey'));
    }
    error = error.join('\n') + stylize('', 'reset') + '\n';

    message += stylize(ctx.type + 'Error: ' + ctx.message, 'red');
    if (ctx.filename) {
        message += stylize(' in ', 'red') + ctx.filename +
        stylize(' on line ' + ctx.line + ', column ' + (ctx.column + 1) + ':', 'grey');
    }

    message += '\n' + error;

    if (ctx.callLine) {
        message += stylize('from ', 'red') + (ctx.filename || '') + '/n';
        message += stylize(ctx.callLine, 'grey') + ' ' + ctx.callExtract + '/n';
    }

    return message;
}

function writeError(ctx, options) {
    options = options || {};
    if (options.silent) {
        return;
    }
    var message = formatError(ctx, options);
    throw new Error(message);
}

function loadStyleSheet(sheet, callback, reload, remaining) {
    var endOfPath = Math.max(name.lastIndexOf('/'), name.lastIndexOf('\\')),
        sheetName = name.slice(0, endOfPath + 1) + sheet.href,
        contents = sheet.contents || {},
        input = readFile(sheetName);

    input = input.replace(/^\xEF\xBB\xBF/, '');

    contents[sheetName] = input;

    var parser = new less.Parser({
        paths: [sheet.href.replace(/[\w\.-]+$/, '')],
        contents: contents
    });
    parser.parse(input, function (e, root) {
        if (e) {
            return writeError(e);
        }
        //try {
        callback(e, root, input, sheet, {local: false, lastModified: 0, remaining: remaining}, sheetName);
        //} catch (e) {
        //writeError(e);
        //log.error(e);
        //}
    });
}

less.Parser.fileLoader = function (file, currentFileInfo, callback, env) {

    var href = file;
    if (currentFileInfo && currentFileInfo.currentDirectory && !/^\//.test(file)) {
        href = less.modules.path.join(currentFileInfo.currentDirectory, file);
    }

    var path = less.modules.path.dirname(href);

    var newFileInfo = {
        currentDirectory: path + '/',
        filename: href
    };

    if (currentFileInfo) {
        newFileInfo.entryPath = currentFileInfo.entryPath;
        newFileInfo.rootpath = currentFileInfo.rootpath;
        newFileInfo.rootFilename = currentFileInfo.rootFilename;
        newFileInfo.relativeUrls = currentFileInfo.relativeUrls;
    } else {
        newFileInfo.entryPath = path;
        newFileInfo.rootpath = less.rootpath || path;
        newFileInfo.rootFilename = href;
        newFileInfo.relativeUrls = env.relativeUrls;
    }

    var j = file.lastIndexOf('/');
    if (newFileInfo.relativeUrls && !/^(?:[a-z-]+:|\/)/.test(file) && j != -1) {
        var relativeSubDirectory = file.slice(0, j + 1);
        newFileInfo.rootpath = newFileInfo.rootpath + relativeSubDirectory; // append (sub|sup) directory path of imported file
    }
    newFileInfo.currentDirectory = path;
    newFileInfo.filename = href;

    var data = null;
    try {
        data = readFile(href);
    } catch (e) {
        log.error(e);
        callback({type: 'File', message: "'" + less.modules.path.basename(href) + "' wasn't found"});
        return;
    }

    try {
        callback(null, data, href, newFileInfo, {lastModified: 0});
    } catch (e) {
        callback(e, null, href);
    }
};


function writeFile(filename, content) {
    var f = new File(filename);
    f.open('w');
    f.write(content);
    f.close();
}

// Command line integration via Rhino
var compile = function (args) {

    var options = {
        depends: false,
        compress: false,
        cleancss: false,
        max_line_len: -1,
        optimization: 1,
        silent: false,
        verbose: false,
        lint: false,
        paths: [],
        color: true,
        strictImports: false,
        rootpath: '',
        relativeUrls: false,
        ieCompat: true,
        strictMath: false,
        strictUnits: false
    };
    var continueProcessing = true,
        currentErrorcode;

    var checkArgFunc = function (arg, option) {
        if (!option) {
            print(arg + " option requires a parameter");
            continueProcessing = false;
            return false;
        }
        return true;
    };

    var checkBooleanArg = function (arg) {
        var onOff = /^((on|t|true|y|yes)|(off|f|false|n|no))$/i.exec(arg);
        if (!onOff) {
            print(" unable to parse " + arg + " as a boolean. use one of on/t/true/y/yes/off/f/false/n/no");
            continueProcessing = false;
            return false;
        }
        return Boolean(onOff[2]);
    };

    var warningMessages = "";
    var sourceMapFileInline = false;

    args = args.filter(function (arg) {
        var match = arg.match(/^-I(.+)$/);

        if (match) {
            options.paths.push(match[1]);
            return false;
        }

        match = arg.match(/^--?([a-z][0-9a-z-]*)(?:=(.*))?$/i);
        if (match) {
            arg = match[1];
        } // was (?:=([^\s]*)), check!
        else {
            return arg;
        }

        switch (arg) {
            case 'v':
            case 'version':
                console.log("lessc " + less.version.join('.') + " (Less Compiler) [JavaScript]");
                continueProcessing = false;
                break;
            case 'verbose':
                options.verbose = true;
                break;
            case 's':
            case 'silent':
                options.silent = true;
                break;
            case 'l':
            case 'lint':
                options.lint = true;
                break;
            case 'strict-imports':
                options.strictImports = true;
                break;
            case 'h':
            case 'help':
                //TODO
//                require('../lib/less/lessc_helper').printUsage();
                continueProcessing = false;
                break;
            case 'x':
            case 'compress':
                options.compress = true;
                break;
            case 'M':
            case 'depends':
                options.depends = true;
                break;
            case 'yui-compress':
                warningMessages += "yui-compress option has been removed. assuming clean-css.";
                options.cleancss = true;
                break;
            case 'clean-css':
                options.cleancss = true;
                break;
            case 'max-line-len':
                if (checkArgFunc(arg, match[2])) {
                    options.maxLineLen = parseInt(match[2], 10);
                    if (options.maxLineLen <= 0) {
                        options.maxLineLen = -1;
                    }
                }
                break;
            case 'no-color':
                options.color = false;
                break;
            case 'no-ie-compat':
                options.ieCompat = false;
                break;
            case 'no-js':
                options.javascriptEnabled = false;
                break;
            case 'include-path':
                if (checkArgFunc(arg, match[2])) {
                    options.paths = match[2].split(os.type().match(/Windows/) ? ';' : ':')
                        .map(function (p) {
                            if (p) {
//                                    return path.resolve(process.cwd(), p);
                                return p;
                            }
                        });
                }
                break;
            case 'O0':
                options.optimization = 0;
                break;
            case 'O1':
                options.optimization = 1;
                break;
            case 'O2':
                options.optimization = 2;
                break;
            case 'line-numbers':
                if (checkArgFunc(arg, match[2])) {
                    options.dumpLineNumbers = match[2];
                }
                break;
            case 'source-map':
                if (!match[2]) {
                    options.sourceMap = true;
                } else {
                    options.sourceMap = match[2];
                }
                break;
            case 'source-map-rootpath':
                if (checkArgFunc(arg, match[2])) {
                    options.sourceMapRootpath = match[2];
                }
                break;
            case 'source-map-basepath':
                if (checkArgFunc(arg, match[2])) {
                    options.sourceMapBasepath = match[2];
                }
                break;
            case 'source-map-map-inline':
                sourceMapFileInline = true;
                options.sourceMap = true;
                break;
            case 'source-map-less-inline':
                options.outputSourceFiles = true;
                break;
            case 'source-map-url':
                if (checkArgFunc(arg, match[2])) {
                    options.sourceMapURL = match[2];
                }
                break;
            case 'source-map-output-map-file':
                if (checkArgFunc(arg, match[2])) {
                    options.writeSourceMap = function (sourceMapContent) {
                        writeFile(match[2], sourceMapContent);
                    };
                }
                break;
            case 'rp':
            case 'rootpath':
                if (checkArgFunc(arg, match[2])) {
                    options.rootpath = match[2].replace(/\\/g, '/');
                }
                break;
            case "ru":
            case "relative-urls":
                options.relativeUrls = true;
                break;
            case "sm":
            case "strict-math":
                if (checkArgFunc(arg, match[2])) {
                    options.strictMath = checkBooleanArg(match[2]);
                }
                break;
            case "su":
            case "strict-units":
                if (checkArgFunc(arg, match[2])) {
                    options.strictUnits = checkBooleanArg(match[2]);
                }
                break;
            default:
                console.log('invalid option ' + arg);
                continueProcessing = false;
        }
    });

    if (!continueProcessing) {
        return;
    }

    var name = args[0];
    if (name && name != '-') {
//        name = path.resolve(process.cwd(), name);
    }
    var output = args[1];
    var outputbase = args[1];
    if (output) {
        options.sourceMapOutputFilename = output;
//        output = path.resolve(process.cwd(), output);
        if (warningMessages) {
            console.log(warningMessages);
        }
    }

//  options.sourceMapBasepath = process.cwd();
//    options.sourceMapBasepath = '';

    if (options.sourceMap === true) {
        console.log("output: " + output);
        if (!output && !sourceMapFileInline) {
            console.log("the sourcemap option only has an optional filename if the css filename is given");
            return;
        }
        options.sourceMapFullFilename = options.sourceMapOutputFilename + ".map";
        options.sourceMap = less.modules.path.basename(options.sourceMapFullFilename);
    } else if (options.sourceMap) {
        options.sourceMapOutputFilename = options.sourceMap;
    }


    if (!name) {
        console.log("lessc: no inout files");
        console.log("");
        // TODO
//        require('../lib/less/lessc_helper').printUsage();
        currentErrorcode = 1;
        return;
    }

//    var ensureDirectory = function (filepath) {
//        var dir = path.dirname(filepath),
//                cmd,
//                existsSync = fs.existsSync || path.existsSync;
//        if (!existsSync(dir)) {
//            if (mkdirp === undefined) {
//                try {mkdirp = require('mkdirp');}
//                catch(e) { mkdirp = null; }
//            }
//            cmd = mkdirp && mkdirp.sync || fs.mkdirSync;
//            cmd(dir);
//        }
//    };

    if (options.depends) {
        if (!outputbase) {
            console.log("option --depends requires an output path to be specified");
            return;
        }
        console.log(outputbase + ": ");
    }

    if (!name) {
        console.log('No files present in the fileset');
        quit(1);
    }

    var input = null;
    try {
        input = readFile(name, 'utf-8');
    } catch (e) {
        log.error(e);
        quit(1);
    }

    options.filename = name;
    var result;
    var parser = new less.Parser(options);
    parser.parse(input, function (e, root) {
        if (e) {
            log.info(e);
            writeError(e, options);
            quit(1);
        } else {
            result = root.toCSS(options);
            if (output) {
                writeFile(output, result);
                console.log("Written to " + output);
            } else {
                print(result);
            }
            quit(0);
        }
    }, {
        globalVars: {'self-class': fuseState.currentUnit + '-unit'}
    });
};
