support/compile.js
function parseConditionals(js) {
  var lines = js.split('\n')
    , len = lines.length
    , buffer = true
    , browser = false
    , buf = []
    , line
    , cond;

  for (var i = 0; i < len; ++i) {
    line = lines[i];
    if (/^ *\/\/ *if *(node|browser)/gm.exec(line)) {
      cond = RegExp.$1;
      buffer = browser = 'browser' == cond;
    } else if (/^ *\/\/ *end/.test(line)) {
      buffer = true;
      browser = false;
    } else if (browser) {
      buf.push(line.replace(/^( *)\/\//, '$1'));
    } else if (buffer) {
      buf.push(line);
    }
  }

  return buf.join('\n');
}
function parseConditionals(js) {
  var lines = js.split('\n')
    , len = lines.length
    , buffer = true
    , browser = false
    , buf = []
    , line
    , cond;

  for (var i = 0; i < len; ++i) {
    line = lines[i];
    if (/^ *\/\/ *if *(node|browser)/gm.exec(line)) {
      cond = RegExp.$1;
      buffer = browser = 'browser' == cond;
    } else if (/^ *\/\/ *end/.test(line)) {
      buffer = true;
      browser = false;
    } else if (browser) {
      buf.push(line.replace(/^( *)\/\//, '$1'));
    } else if (buffer) {
      buf.push(line);
    }
  }

  return buf.join('\n');
}
function parseConditionals ( js ) { var lines = js . split ( '\n' ) , len = lines . length , buffer = true , browser = false , buf = [ ] , line , cond ; for ( var i = 0 ; i < len ; ++ i ) { line = lines [ i ] ; if ( / ^ *\/\/ *if *(node|browser) / gm . exec ( line ) ) { cond = RegExp . $1 ; buffer = browser = 'browser' == cond ; } else if ( / ^ *\/\/ *end / . test ( line ) ) { buffer = true ; browser = false ; } else if ( browser ) { buf . push ( line . replace ( / ^( *)\/\/ / , '$1' ) ) ; } else if ( buffer ) { buf . push ( line ) ; } } return buf . join ( '\n' ) ; }
Parse the given `js`, currently supporting:

'if' ['node' | 'browser']
'end'
Parse the given js currently supporting :