text: /**
   * @license
   * Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
   * Build: `lodash underscore exports="amd,commonjs,global,node" -o ./dist/lodash.underscore.js`
   * Copyright 2012-2014 The Dojo Foundation <http://dojofoundation.org/>
   * Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE>
   * Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
   * Available under MIT license <http://lodash.com/license>
   */
  ;(function() {
  
    /** Used as a safe reference for `undefined` in pre ES5 environments */
    var undefined;
  
    /** Used to compose bitmasks for wrapper metadata */
    var BIND_FLAG = 1,
        BIND_KEY_FLAG = 2,
        CURRY_FLAG = 4,
        CURRY_BOUND_FLAG = 8,
        PARTIAL_FLAG = 16,
        PARTIAL_RIGHT_FLAG = 32;
  
    /** Used as the semantic version number */
    var version = '2.4.1';
  
    /** Used as the property name for wrapper metadata */
    var expando = '__lodash@' + version + '__';
  
    /** Used by methods to exit iteration */
    var breakIndicator = expando + 'breaker__';
  
    /** Used to generate unique IDs */
    var idCounter = 0;
  
    /** Used to match HTML entities and HTML characters */
    var reEscapedHtml = /&(?:amp|lt|gt|quot|#x27);/g,
        reUnescapedHtml = /[&<>"']/g;
  
    /** Used to match template delimiters */
    var reEscape = /<%-([\s\S]+?)%>/g,
        reEvaluate = /<%([\s\S]+?)%>/g,
        reInterpolate = /<%=([\s\S]+?)%>/g;
  
    /** Used to ensure capturing order of template delimiters */
    var reNoMatch = /($^)/;
  
    /** Used to match unescaped characters in compiled string literals */
    var reUnescapedString = /['\n\r\t\u2028\u2029\\]/g;
  
    /** `Object#toString` result shortcuts */
    var argsClass = '[object Arguments]',
        arrayClass = '[object Array]',
        boolClass = '[object Boolean]',
        dateClass = '[object Date]',
        funcClass = '[object Function]',
        numberClass = '[object Number]',
        objectClass = '[object Object]',
        regexpClass = '[object RegExp]',
        stringClass = '[object String]';
  
    /**
     * Used to convert characters to HTML entities.
     *
     * Note: Though the ">" character is escaped for symmetry, characters like
     * ">", "`", and "/" don't require escaping in HTML and have no special meaning
     * unless they're part of a tag or unquoted attribute value.
     * See [Mathias' article](http://mathiasbynens.be/notes/ambiguous-ampersands)
     * (under "semi-related fun fact") for more details.
     */
    var htmlEscapes = {
      '&': '&amp;',
      '<': '&lt;',
      '>': '&gt;',
      '"': '&quot;',
      "'": '&#x27;'
    };
  
    /** Used to convert HTML entities to characters */
    var htmlUnescapes = {
      '&amp;': '&',
      '&lt;': '<',
      '&gt;': '>',
      '&quot;': '"',
      '&#x27;': "'"
    };
  
    /** Used to determine if values are of the language type Object */
    var objectTypes = {
      'function': true,
      'object': true
    };
  
    /** Used to escape characters for inclusion in compiled string literals */
    var stringEscapes = {
      '\\': '\\',
      "'": "'",
      '\n': 'n',
      '\r': 'r',
      '\t': 't',
      '\u2028': 'u2028',
      '\u2029': 'u2029'
    };
  
    /** Used as a reference to the global object */
    var root = (objectTypes[typeof window] && window) || this;
  
    /** Detect free variable `exports` */
    var freeExports = objectTypes[typeof exports] && exports && !exports.nodeType && exports;
  
    /** Detect free variable `module` */
    var freeModule = objectTypes[typeof module] && module && !module.nodeType && module;
  
    /** Detect free variable `global` from Node.js or Browserified code and use it as `root` */
    var freeGlobal = freeExports && freeModule && typeof global == 'object' && global;
    if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal || freeGlobal.self === freeGlobal)) {
      root = freeGlobal;
    }
  
    /** Detect the popular CommonJS extension `module.exports` */
    var moduleExports = freeModule && freeModule.exports === freeExports && freeExports;
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * The base implementation of `compareAscending` used to compare values and
     * sort them in ascending order without guaranteeing a stable sort.
     *
     * @private
     * @param {*} a The value to compare to `b`.
     * @param {*} b The value to compare to `a`.
     * @returns {number} Returns the sort order indicator for `a`.
     */
    function baseCompareAscending(a, b) {
      if (a !== b) {
        if (a > b || typeof a == 'undefined') {
          return 1;
        }
        if (a < b || typeof b == 'undefined') {
          return -1;
        }
      }
      return 0;
    }
  
    /**
     * The base implementation of `_.indexOf` without support for binary searches.
     *
     * @private
     * @param {Array} array The array to search.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {number} Returns the index of the matched value or `-1`.
     */
    function baseIndexOf(array, value, fromIndex) {
      var index = (fromIndex || 0) - 1,
          length = array ? array.length : 0;
  
      while (++index < length) {
        if (array[index] === value) {
          return index;
        }
      }
      return -1;
    }
  
    /**
     * Used by `sortBy` to compare transformed elements of a collection and stable
     * sort them in ascending order.
     *
     * @private
     * @param {Object} a The object to compare to `b`.
     * @param {Object} b The object to compare to `a`.
     * @returns {number} Returns the sort order indicator for `a`.
     */
    function compareAscending(a, b) {
      return baseCompareAscending(a.criteria, b.criteria) || a.index - b.index;
    }
  
    /**
     * Used by `escape` to convert characters to HTML entities.
     *
     * @private
     * @param {string} match The matched character to escape.
     * @returns {string} Returns the escaped character.
     */
    function escapeHtmlChar(match) {
      return htmlEscapes[match];
    }
  
    /**
     * Used by `template` to escape characters for inclusion in compiled
     * string literals.
     *
     * @private
     * @param {string} match The matched character to escape.
     * @returns {string} Returns the escaped character.
     */
    function escapeStringChar(match) {
      return '\\' + stringEscapes[match];
    }
  
    /**
     * Used by `unescape` to convert HTML entities to characters.
     *
     * @private
     * @param {string} match The matched character to unescape.
     * @returns {string} Returns the unescaped character.
     */
    function unescapeHtmlChar(match) {
      return htmlUnescapes[match];
    }
  
    /*--------------------------------------------------------------------------*/
  
    /** Used for native method references */
    var arrayRef = Array.prototype,
        objectProto = Object.prototype;
  
    /** Used to restore the original `_` reference in `noConflict` */
    var oldDash = root._;
  
    /** Used to resolve the internal [[Class]] of values */
    var toString = objectProto.toString;
  
    /** Used to detect if a method is native */
    var reNative = RegExp('^' +
      String(toString)
        .replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
        .replace(/toString|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
    );
  
    /** Native method shortcuts */
    var ceil = Math.ceil,
        floor = Math.floor,
        fnToString = Function.prototype.toString,
        hasOwnProperty = objectProto.hasOwnProperty,
        push = arrayRef.push,
        propertyIsEnumerable = objectProto.propertyIsEnumerable,
        splice = arrayRef.splice;
  
    /* Native method shortcuts for methods with the same name as other `lodash` methods */
    var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate,
        nativeIsArray = isNative(nativeIsArray = Array.isArray) && nativeIsArray,
        nativeIsFinite = root.isFinite,
        nativeIsNaN = root.isNaN,
        nativeKeys = isNative(nativeKeys = Object.keys) && nativeKeys,
        nativeMax = Math.max,
        nativeMin = Math.min,
        nativeNow = isNative(nativeNow = Date.now) && nativeNow,
        nativeRandom = Math.random;
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Creates a `lodash` object which wraps the given value to enable intuitive
     * method chaining.
     *
     * In addition to Lo-Dash methods, wrappers also have the following `Array` methods:
     * `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`,
     * and `unshift`
     *
     * Chaining is supported in custom builds as long as the `value` method is
     * implicitly or explicitly included in the build.
     *
     * The chainable wrapper functions are:
     * `after`, `assign`, `bind`, `bindAll`, `bindKey`, `chain`, `compact`,
     * `compose`, `concat`, `constant`, `countBy`, `create`, `createCallback`,
     * `curry`, `debounce`, `defaults`, `defer`, `delay`, `difference`, `filter`,
     * `flatten`, `forEach`, `forEachRight`, `forIn`, `forInRight`, `forOwn`,
     * `forOwnRight`, `functions`, `groupBy`, `indexBy`, `initial`, `intersection`,
     * `invert`, `invoke`, `keys`, `map`, `mapValues`, `match`, `max`, `memoize`,
     * `merge`, `min`, `noop`, `object`, `omit`, `once`, `pairs`, `partial`,
     * `partialRight`, `pick`, `pluck`, `property`, `pull`, `push`, `range`,
     * `reject`, `remove`, `rest`, `reverse`, `shuffle`, `slice`, `sort`, `sortBy`,
     * `splice`, `tap`, `throttle`, `times`, `toArray`, `transform`, `union`,
     * `uniq`, `unshift`, `unzip`, `values`, `where`, `without`, `wrap`, `xor`,
     * and `zip`
     *
     * The non-chainable wrapper functions are:
     * `capitalize`, `clone`, `cloneDeep`, `contains`, `escape`, `every`, `find`,
     * `findIndex`, `findKey`, `findLast`, `findLastIndex`, `findLastKey`, `has`,
     * `identity`, `indexOf`, `isArguments`, `isArray`, `isBoolean`, `isDate`,
     * `isElement`, `isEmpty`, `isEqual`, `isFinite`, `isFunction`, `isNaN`,
     * `isNull`, `isNumber`, `isObject`, `isPlainObject`, `isRegExp`, `isString`,
     * `isUndefined`, `join`, `lastIndexOf`, `mixin`, `noConflict`, `now`,
     * `parseInt`, `pop`, `random`, `reduce`, `reduceRight`, `result`, `shift`,
     * `size`, `some`, `sortedIndex`, `runInContext`, `template`, `trim`,
     * `trimLeft`, `trimRight`, `unescape`, `uniqueId`, and `value`
     *
     * The wrapper functions `first`, `last`, and `sample` return wrapped values
     * when `n` is provided, otherwise they return unwrapped values.
     *
     * Explicit chaining can be enabled by using the `_.chain` method.
     *
     * @name _
     * @constructor
     * @category Chaining
     * @param {*} value The value to wrap in a `lodash` instance.
     * @returns {Object} Returns a `lodash` instance.
     * @example
     *
     * var wrapped = _([1, 2, 3]);
     *
     * // returns an unwrapped value
     * wrapped.reduce(function(sum, num) {
     *   return sum + num;
     * });
     * // => 6
     *
     * // returns a wrapped value
     * var squares = wrapped.map(function(num) {
     *   return num * num;
     * });
     *
     * _.isArray(squares);
     * // => false
     *
     * _.isArray(squares.value());
     * // => true
     */
    function lodash(value) {
      return (value instanceof lodash)
        ? value
        : new lodashWrapper(value);
    }
  
    /**
     * A fast path for creating `lodash` wrapper objects.
     *
     * @private
     * @param {*} value The value to wrap in a `lodash` instance.
     * @param {boolean} [chainAll=false] A flag to enable chaining for all methods
     * @returns {Object} Returns a `lodash` instance.
     */
    function lodashWrapper(value, chainAll) {
      this.__chain__ = !!chainAll;
      this.__wrapped__ = value;
    }
    // ensure `new lodashWrapper` is an instance of `lodash`
    lodashWrapper.prototype = lodash.prototype;
  
    /**
     * An object used to flag environments features.
     *
     * @static
     * @memberOf _
     * @type Object
     */
    var support = {};
  
    (function() {
      var object = { '0': 1, 'length': 1 };
  
      /**
       * Detect if `Array#shift` and `Array#splice` augment array-like objects correctly.
       *
       * Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()`
       * and `splice()` functions that fail to remove the last element, `value[0]`,
       * of array-like objects even though the `length` property is set to `0`.
       * The `shift()` method is buggy in IE 8 compatibility mode, while `splice()`
       * is buggy regardless of mode in IE < 9 and buggy in compatibility mode in IE 9.
       *
       * @memberOf _.support
       * @type boolean
       */
      support.spliceObjects = (splice.call(object, 0, 1), !object[0]);
    }(1));
  
    /**
     * By default, the template delimiters used by Lo-Dash are similar to those in
     * embedded Ruby (ERB). Change the following template settings to use alternative
     * delimiters.
     *
     * @static
     * @memberOf _
     * @type Object
     */
    lodash.templateSettings = {
  
      /**
       * Used to detect `data` property values to be HTML-escaped.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'escape': reEscape,
  
      /**
       * Used to detect code to be evaluated.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'evaluate': reEvaluate,
  
      /**
       * Used to detect `data` property values to inject.
       *
       * @memberOf _.templateSettings
       * @type RegExp
       */
      'interpolate': reInterpolate,
  
      /**
       * Used to reference the data object in the template text.
       *
       * @memberOf _.templateSettings
       * @type string
       */
      'variable': ''
    };
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * The base implementation of `_.bind` that creates the bound function and
     * sets its meta data.
     *
     * @private
     * @param {Array} data The metadata array.
     * @returns {Function} Returns the new bound function.
     */
    function baseBind(data) {
      var func = data[0],
          thisArg = data[3],
          partialArgs = data[4];
  
      function bound() {
        // `Function#bind` spec
        // http://es5.github.io/#x15.3.4.5
        if (partialArgs) {
          // avoid `arguments` object deoptimizations by using `slice` instead
          // of `Array.prototype.slice.call` and not assigning `arguments` to a
          // variable as a ternary expression
          var args = slice(partialArgs);
          push.apply(args, arguments);
        }
        // mimic the constructor's `return` behavior
        // http://es5.github.io/#x13.2.2
        if (this instanceof bound) {
          // ensure `new bound` is an instance of `func`
          var thisBinding = baseCreate(func.prototype),
              result = func.apply(thisBinding, args || arguments);
          return isObject(result) ? result : thisBinding;
        }
        return func.apply(thisArg, args || arguments);
      }
      return bound;
    }
  
    /**
     * The base implementation of `_.create` without support for assigning
     * properties to the created object.
     *
     * @private
     * @param {Object} prototype The object to inherit from.
     * @returns {Object} Returns the new object.
     */
    function baseCreate(prototype) {
      return isObject(prototype) ? nativeCreate(prototype) : {};
    }
    // fallback for environments without `Object.create`
    if (!nativeCreate) {
      baseCreate = (function() {
        function Object() {}
        return function(prototype) {
          if (isObject(prototype)) {
            Object.prototype = prototype;
            var result = new Object;
            Object.prototype = null;
          }
          return result || root.Object();
        };
      }());
    }
  
    /**
     * The base implementation of `_.createCallback` without support for creating
     * "_.pluck" or "_.where" style callbacks.
     *
     * @private
     * @param {*} [func=identity] The value to convert to a callback.
     * @param {*} [thisArg] The `this` binding of the created callback.
     * @param {number} [argCount] The number of arguments the callback accepts.
     * @returns {Function} Returns a callback function.
     */
    function baseCreateCallback(func, thisArg, argCount) {
      if (typeof func != 'function') {
        return identity;
      }
      // exit early for no `thisArg` or already bound by `Function#bind`
      if (typeof thisArg == 'undefined' || !('prototype' in func)) {
        return func;
      }
      switch (argCount) {
        case 1: return function(value) {
          return func.call(thisArg, value);
        };
        case 2: return function(a, b) {
          return func.call(thisArg, a, b);
        };
        case 3: return function(value, index, collection) {
          return func.call(thisArg, value, index, collection);
        };
        case 4: return function(accumulator, value, index, collection) {
          return func.call(thisArg, accumulator, value, index, collection);
        };
      }
      return bind(func, thisArg);
    }
  
    /**
     * The base implementation of `createWrapper` that creates the wrapper and
     * sets its meta data.
     *
     * @private
     * @param {Array} data The metadata array.
     * @returns {Function} Returns the new function.
     */
    function baseCreateWrapper(data) {
      var func = data[0],
          bitmask = data[1],
          arity = data[2],
          thisArg = data[3],
          partialArgs = data[4],
          partialRightArgs = data[5];
  
      var isBind = bitmask & BIND_FLAG,
          isBindKey = bitmask & BIND_KEY_FLAG,
          isCurry = bitmask & CURRY_FLAG,
          isCurryBound = bitmask & CURRY_BOUND_FLAG,
          key = func;
  
      function bound() {
        var thisBinding = isBind ? thisArg : this;
        if (partialArgs) {
          var args = slice(partialArgs);
          push.apply(args, arguments);
        }
        if (partialRightArgs || isCurry) {
          args || (args = slice(arguments));
          if (partialRightArgs) {
            push.apply(args, partialRightArgs);
          }
          var argsLength = arguments.length;
          if (isCurry && argsLength < arity) {
            bitmask |= PARTIAL_FLAG;
            bitmask &= ~PARTIAL_RIGHT_FLAG
            if (!isCurryBound) {
              bitmask &= ~(BIND_FLAG | BIND_KEY_FLAG);
            }
            var newArity = nativeMax(0, arity - argsLength);
            return baseCreateWrapper([func, bitmask, newArity, thisArg, args]);
          }
        }
        args || (args = arguments);
        if (isBindKey) {
          func = thisBinding[key];
        }
        if (this instanceof bound) {
          thisBinding = baseCreate(func.prototype);
          var result = func.apply(thisBinding, args);
          return isObject(result) ? result : thisBinding;
        }
        return func.apply(thisBinding, args);
      }
      return bound;
    }
  
    /**
     * The base implementation of `_.difference` that accepts a single array
     * of values to exclude.
     *
     * @private
     * @param {Array} array The array to process.
     * @param {Array} [values] The array of values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     */
    function baseDifference(array, values) {
      var index = -1,
          indexOf = getIndexOf(),
          length = array ? array.length : 0,
          result = [];
  
      while (++index < length) {
        var value = array[index];
        if (indexOf(values, value) < 0) {
          result.push(value);
        }
      }
      return result;
    }
  
    /**
     * The base implementation of `_.forEach` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} callback The function called per iteration.
     * @returns {Array|Object|string} Returns `collection`.
     */
    function baseEach(collection, callback) {
      var index = -1,
          iterable = collection,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (++index < length) {
          if (callback(iterable[index], index, collection) === breakIndicator) {
            break;
          }
        }
      } else {
        baseForOwn(collection, callback);
      }
      return collection;
    }
  
    /**
     * The base implementation of `_.forEachEach` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} callback The function called per iteration.
     * @returns {Array|Object|string} Returns `collection`.
     */
    function baseEachRight(collection, callback) {
      var iterable = collection,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (length--) {
          if (callback(iterable[length], length, collection) === breakIndicator) {
            break;
          }
        }
      } else {
        baseForOwnRight(collection, callback);
      }
      return collection;
    }
  
    /**
     * The base implementation of `_.flatten` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Array} array The array to flatten.
     * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level.
     * @param {boolean} [isStrict=false] A flag to restrict flattening to arrays and `arguments` objects.
     * @param {number} [fromIndex=0] The index to start from.
     * @returns {Array} Returns a new flattened array.
     */
    function baseFlatten(array, isShallow, isStrict, fromIndex) {
      var index = (fromIndex || 0) - 1,
          length = array ? array.length : 0,
          result = [];
  
      while (++index < length) {
        var value = array[index];
  
        if (value && typeof value == 'object' && typeof value.length == 'number'
            && (isArray(value) || isArguments(value))) {
          // recursively flatten arrays (susceptible to call stack limits)
          if (!isShallow) {
            value = baseFlatten(value, isShallow, isStrict);
          }
          var valIndex = -1,
              valLength = value.length,
              resIndex = result.length;
  
          result.length += valLength;
          while (++valIndex < valLength) {
            result[resIndex++] = value[valIndex];
          }
        } else if (!isStrict) {
          result.push(value);
        }
      }
      return result;
    }
  
    /**
     * The base implementation of `_.forOwn` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} callback The function called per iteration.
     * @returns {Object} Returns `object`.
     */
    function baseForOwn(object, callback) {
      var index = -1,
          props = keys(object),
          length = props.length;
  
      while (++index < length) {
        var key = props[index];
        if (callback(object[key], key, object) === breakIndicator) {
          break;
        }
      }
      return object;
    }
  
    /**
     * The base implementation of `_.forOwnRight` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} callback The function called per iteration.
     * @returns {Object} Returns `object`.
     */
    function baseForOwnRight(object, callback) {
      var props = keys(object),
          length = props.length;
  
      while (length--) {
        var key = props[length];
        if (callback(object[key], key, object) === breakIndicator) {
          break;
        }
      }
      return object;
    }
  
    /**
     * The base implementation of `_.isEqual`, without support for `thisArg` binding,
     * that allows partial "_.where" style comparisons.
     *
     * @private
     * @param {*} a The value to compare.
     * @param {*} b The other value to compare.
     * @param {Function} [callback] The function to customize comparing values.
     * @param {Function} [isWhere=false] A flag to indicate performing partial comparisons.
     * @param {Array} [stackA=[]] Tracks traversed `a` objects.
     * @param {Array} [stackB=[]] Tracks traversed `b` objects.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     */
    function baseIsEqual(a, b, stackA, stackB) {
      if (a === b) {
        return a !== 0 || (1 / a == 1 / b);
      }
      var type = typeof a,
          otherType = typeof b;
  
      if (a === a &&
          !(a && (type == 'function' || type == 'object')) &&
          !(b && (otherType == 'function' || otherType == 'object'))) {
        return false;
      }
      if (a == null || b == null) {
        return a === b;
      }
      var className = toString.call(a),
          otherClass = toString.call(b);
  
      if (className != otherClass) {
        return false;
      }
      switch (className) {
        case boolClass:
        case dateClass:
          return +a == +b;
  
        case numberClass:
          return a != +a
            ? b != +b
            : (a == 0 ? (1 / a == 1 / b) : a == +b);
  
        case regexpClass:
        case stringClass:
          return a == String(b);
      }
      var isArr = className == arrayClass;
      if (!isArr) {
        var aWrapped = a instanceof lodash,
            bWrapped = b instanceof lodash;
  
        if (aWrapped || bWrapped) {
          return baseIsEqual(aWrapped ? a.__wrapped__ : a, bWrapped ? b.__wrapped__ : b, stackA, stackB);
        }
        if (className != objectClass) {
          return false;
        }
        var ownCtorA = hasOwnProperty.call(a, 'constructor'),
            ownCtorB = hasOwnProperty.call(b, 'constructor');
  
        if (ownCtorA !== ownCtorB) {
          return false;
        }
        if (!ownCtorA) {
          var ctorA = a.constructor,
              ctorB = b.constructor;
  
          if (ctorA != ctorB &&
                !(isFunction(ctorA) && ctorA instanceof ctorA && isFunction(ctorB) && ctorB instanceof ctorB) &&
                ('constructor' in a && 'constructor' in b)
              ) {
            return false;
          }
        }
      }
      stackA || (stackA = []);
      stackB || (stackB = []);
  
      var length = stackA.length;
      while (length--) {
        if (stackA[length] == a) {
          return stackB[length] == b;
        }
      }
      var result = true,
          size = 0;
  
      stackA.push(a);
      stackB.push(b);
  
      if (isArr) {
        size = b.length;
        result = size == a.length;
  
        if (result) {
          while (size--) {
            if (!(result = baseIsEqual(a[size], b[size], stackA, stackB))) {
              break;
            }
          }
        }
      }
      else {
        baseForIn(b, function(value, key, b) {
          if (hasOwnProperty.call(b, key)) {
            size++;
            return !(result = hasOwnProperty.call(a, key) && baseIsEqual(a[key], value, stackA, stackB)) && breakIndicator;
          }
        });
  
        if (result) {
          baseForIn(a, function(value, key, a) {
            if (hasOwnProperty.call(a, key)) {
              return !(result = --size > -1) && breakIndicator;
            }
          });
        }
      }
      stackA.pop();
      stackB.pop();
      return result;
    }
  
    /**
     * The base implementation of `_.random` without argument juggling or support
     * for returning floating-point numbers.
     *
     * @private
     * @param {number} min The minimum possible value.
     * @param {number} max The maximum possible value.
     * @returns {number} Returns a random number.
     */
    function baseRandom(min, max) {
      return min + floor(nativeRandom() * (max - min + 1));
    }
  
    /**
     * The base implementation of `_.uniq` without support for callback shorthands
     * or `thisArg` binding.
     *
     * @private
     * @param {Array} array The array to process.
     * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted.
     * @param {Function} [callback] The function called per iteration.
     * @returns {Array} Returns a duplicate-value-free array.
     */
    function baseUniq(array, isSorted, callback) {
      var index = -1,
          indexOf = getIndexOf(),
          length = array ? array.length : 0,
          result = [],
          seen = callback ? [] : result;
  
      while (++index < length) {
        var value = array[index],
            computed = callback ? callback(value, index, array) : value;
  
        if (isSorted
              ? !index || seen[seen.length - 1] !== computed
              : indexOf(seen, computed) < 0
            ) {
          if (callback) {
            seen.push(computed);
          }
          result.push(value);
        }
      }
      return result;
    }
  
    /**
     * Creates a function that aggregates a collection, creating an object composed
     * of keys generated from the results of running each element of the collection
     * through a callback. The given `setter` function sets the keys and values
     * of the composed object.
     *
     * @private
     * @param {Function} setter The setter function.
     * @returns {Function} Returns the new aggregator function.
     */
    function createAggregator(setter) {
      return function(collection, callback, thisArg) {
        var result = {};
  
        callback = createCallback(callback, thisArg, 3);
        var index = -1,
            length = collection ? collection.length : 0;
  
        if (typeof length == 'number') {
          while (++index < length) {
            var value = collection[index];
            setter(result, value, callback(value, index, collection), collection);
          }
        } else {
          baseEach(collection, function(value, key, collection) {
            setter(result, value, callback(value, key, collection), collection);
          });
        }
        return result;
      };
    }
  
    /**
     * Creates a function that, when called, either curries or invokes `func`
     * with an optional `this` binding and partially applied arguments.
     *
     * @private
     * @param {Function|string} func The function or method name to reference.
     * @param {number} bitmask The bitmask of flags to compose.
     *  The bitmask may be composed of the following flags:
     *  1  - `_.bind`
     *  2  - `_.bindKey`
     *  4  - `_.curry`
     *  8  - `_.curry` (bound)
     *  16 - `_.partial`
     *  32 - `_.partialRight`
     * @param {number} [arity] The arity of `func`.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {Array} [partialArgs] An array of arguments to prepend to those
     *  provided to the new function.
     * @param {Array} [partialRightArgs] An array of arguments to append to those
     *  provided to the new function.
     * @returns {Function} Returns the new function.
     */
    function createWrapper(func, bitmask, arity, thisArg, partialArgs, partialRightArgs) {
      var isBind = bitmask & BIND_FLAG,
          isBindKey = bitmask & BIND_KEY_FLAG,
          isPartial = bitmask & PARTIAL_FLAG,
          isPartialRight = bitmask & PARTIAL_RIGHT_FLAG;
  
      if (!isBindKey && !isFunction(func)) {
        throw new TypeError;
      }
      if (isPartial && !partialArgs.length) {
        bitmask &= ~PARTIAL_FLAG;
        isPartial = partialArgs = false;
      }
      if (isPartialRight && !partialRightArgs.length) {
        bitmask &= ~PARTIAL_RIGHT_FLAG;
        isPartialRight = partialRightArgs = false;
      }
      if (arity == null) {
        arity = isBindKey ? 0 : func.length;
      } else if (arity < 0) {
        arity = 0;
      }
      // fast path for `_.bind`
      var newData = [func, bitmask, arity, thisArg, partialArgs, partialRightArgs];
      return (bitmask == BIND_FLAG || bitmask == (BIND_FLAG | PARTIAL_FLAG))
        ? baseBind(newData)
        : baseCreateWrapper(newData);
    }
  
    /**
     * Gets the appropriate "indexOf" function. If the `_.indexOf` method is
     * customized this method returns the custom method, otherwise it returns
     * the `baseIndexOf` function.
     *
     * @private
     * @returns {Function} Returns the "indexOf" function.
     */
    function getIndexOf() {
      var result = (result = lodash.indexOf) === indexOf ? baseIndexOf : result;
      return result;
    }
  
    /**
     * Checks if `value` is a native function.
     *
     * @private
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a native function, else `false`.
     */
    function isNative(value) {
      return typeof value == 'function' && reNative.test(fnToString.call(value));
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Checks if `value` is an `arguments` object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an `arguments` object, else `false`.
     * @example
     *
     * (function() { return _.isArguments(arguments); })(1, 2, 3);
     * // => true
     *
     * _.isArguments([1, 2, 3]);
     * // => false
     */
    function isArguments(value) {
      return value && typeof value == 'object' && typeof value.length == 'number' &&
        toString.call(value) == argsClass || false;
    }
    // fallback for environments that can't detect `arguments` objects by [[Class]]
    if (!isArguments(arguments)) {
      isArguments = function(value) {
        return value && typeof value == 'object' && typeof value.length == 'number' &&
          hasOwnProperty.call(value, 'callee') && !propertyIsEnumerable.call(value, 'callee') || false;
      };
    }
  
    /**
     * The base implementation of `_.forIn` without support for callback
     * shorthands or `thisArg` binding.
     *
     * @private
     * @param {Object} object The object to iterate over.
     * @param {Function} callback The function called per iteration.
     * @returns {Object} Returns `object`.
     */
    var baseForIn = function(object, callback) {
      var result = object;
      if (!isObject(object)) {
        return result;
      }
      for (var key in object) {
        if (callback(object[key], key, object) === breakIndicator) {
          return result;
        }
      }
      return result;
    };
  
    /**
     * A fallback implementation of `Object.keys` which produces an array of the
     * given object's own enumerable property names.
     *
     * @private
     * @type Function
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names.
     */
    var shimKeys = function(object) {
      var result = [];
      if (!isObject(object)) {
        return result;
      }
      for (var key in object) {
        if (hasOwnProperty.call(object, key)) {
          result.push(key);
        }
      }
      return result;
    };
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Creates an array with all falsey values removed. The values `false`, `null`,
     * `0`, `""`, `undefined`, and `NaN` are all falsey.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to compact.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.compact([0, 1, false, 2, '', 3]);
     * // => [1, 2, 3]
     */
    function compact(array) {
      var index = -1,
          length = array ? array.length : 0,
          resIndex = 0,
          result = [];
  
      while (++index < length) {
        var value = array[index];
        if (value) {
          result[resIndex++] = value;
        }
      }
      return result;
    }
  
    /**
     * Creates an array excluding all values of the provided arrays using strict
     * equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to process.
     * @param {...Array} [values] The arrays of values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.difference([1, 2, 3, 4, 5], [5, 2, 10]);
     * // => [1, 3, 4]
     */
    function difference(array) {
      return baseDifference(array, baseFlatten(arguments, true, true, 1));
    }
  
    /**
     * Gets the first element or first `n` elements of an array. If a callback
     * is provided elements at the beginning of the array are returned as long
     * as the callback returns truey. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias head, take
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback] The function called
     *  per element or the number of elements to return. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the first element(s) of `array`.
     * @example
     *
     * _.first([1, 2, 3]);
     * // => 1
     *
     * // returns the first two elements
     * _.first([1, 2, 3], 2);
     * // => [1, 2]
     *
     * // returns elements from the beginning until the callback result is falsey
     * _.first([1, 2, 3], function(num) {
     *   return num < 3;
     * });
     * // => [1, 2]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': true,  'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': false, 'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.first(characters, 'blocked');
     * // => [{ 'name': 'barney', 'blocked': true, 'employer': 'slate' }]
     *
     * // using "_.where" callback shorthand
     * _.pluck(_.first(characters, { 'employer': 'slate' }), 'name');
     * // => ['barney', 'fred']
     */
    function first(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;
  
      if (typeof callback != 'number' && callback != null) {
        var index = -1;
        callback = createCallback(callback, thisArg, 3);
        while (++index < length && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = callback;
        if (n == null || thisArg) {
          return array ? array[0] : undefined;
        }
      }
      return slice(array, 0, n > 0 ? n : 0);
    }
  
    /**
     * Flattens a nested array (the nesting can be to any depth). If `isShallow`
     * is truey, the array will only be flattened a single level. If a callback
     * is provided each element of the array is passed through the callback before
     * flattening. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to flatten.
     * @param {boolean} [isShallow=false] A flag to restrict flattening to a single level.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new flattened array.
     * @example
     *
     * _.flatten([1, [2], [3, [[4]]]]);
     * // => [1, 2, 3, 4];
     *
     * // using `isShallow`
     * _.flatten([1, [2], [3, [[4]]]], true);
     * // => [1, 2, 3, [[4]]];
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 30, 'pets': ['hoppy'] },
     *   { 'name': 'fred',   'age': 40, 'pets': ['baby puss', 'dino'] }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.flatten(characters, 'pets');
     * // => ['hoppy', 'baby puss', 'dino']
     */
    function flatten(array, isShallow, guard) {
      var type = typeof isShallow;
      if ((type == 'number' || type == 'string') && guard && guard[isShallow] === array) {
        isShallow = false;
      }
      return baseFlatten(array, isShallow);
    }
  
    /**
     * Gets the index at which the first occurrence of `value` is found using
     * strict equality for comparisons, i.e. `===`. If the array is already sorted
     * providing `true` for `fromIndex` will run a faster binary search.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {*} value The value to search for.
     * @param {boolean|number} [fromIndex=0] The index to search from or `true`
     *  to perform a binary search on a sorted array.
     * @returns {number} Returns the index of the matched value or `-1`.
     * @example
     *
     * _.indexOf([1, 2, 3, 1, 2, 3], 2);
     * // => 1
     *
     * // using `fromIndex`
     * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3);
     * // => 4
     *
     * // performing a binary search
     * _.indexOf([1, 1, 2, 2, 3, 3], 2, true);
     * // => 2
     */
    function indexOf(array, value, fromIndex) {
      var length = array ? array.length : 0;
      if (typeof fromIndex == 'number') {
        fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex || 0);
      } else if (fromIndex) {
        var index = sortedIndex(array, value);
        return (length && array[index] === value) ? index : -1;
      }
      return baseIndexOf(array, value, fromIndex);
    }
  
    /**
     * Gets all but the last element or last `n` elements of an array. If a
     * callback is provided elements at the end of the array are excluded from
     * the result as long as the callback returns truey. The callback is bound
     * to `thisArg` and invoked with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback=1] The function called
     *  per element or the number of elements to exclude. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a slice of `array`.
     * @example
     *
     * _.initial([1, 2, 3]);
     * // => [1, 2]
     *
     * // excludes the last two elements
     * _.initial([1, 2, 3], 2);
     * // => [1]
     *
     * // excludes elements from the end until the callback fails
     * _.initial([1, 2, 3], function(num) {
     *   return num > 1;
     * });
     * // => [1]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': false, 'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': true,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.initial(characters, 'blocked');
     * // => [{ 'name': 'barney',  'blocked': false, 'employer': 'slate' }]
     *
     * // using "_.where" callback shorthand
     * _.pluck(_.initial(characters, { 'employer': 'na' }), 'name');
     * // => ['barney', 'fred']
     */
    function initial(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;
  
      if (typeof callback != 'number' && callback != null) {
        var index = length;
        callback = createCallback(callback, thisArg, 3);
        while (index-- && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = (callback == null || thisArg) ? 1 : callback || n;
      }
      n = length - n;
      return slice(array, 0, n > 0 ? n : 0);
    }
  
    /**
     * Creates an array of unique values present in all provided arrays using
     * strict equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {...Array} [array] The arrays to inspect.
     * @returns {Array} Returns an array of shared values.
     * @example
     *
     * _.intersection([1, 2, 3], [5, 2, 1, 4], [2, 1]);
     * // => [1, 2]
     */
    function intersection() {
      var args = [],
          argsIndex = -1,
          argsLength = arguments.length;
  
      while (++argsIndex < argsLength) {
        var value = arguments[argsIndex];
         if (isArray(value) || isArguments(value)) {
           args.push(value);
         }
      }
      var array = args[0],
          index = -1,
          indexOf = getIndexOf(),
          length = array ? array.length : 0,
          result = [];
  
      outer:
      while (++index < length) {
        value = array[index];
        if (indexOf(result, value) < 0) {
          var argsIndex = argsLength;
          while (--argsIndex) {
            if (indexOf(args[argsIndex], value) < 0) {
              continue outer;
            }
          }
          result.push(value);
        }
      }
      return result;
    }
  
    /**
     * Gets the last element or last `n` elements of an array. If a callback is
     * provided elements at the end of the array are returned as long as the
     * callback returns truey. The callback is bound to `thisArg` and invoked
     * with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback] The function called
     *  per element or the number of elements to return. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the last element(s) of `array`.
     * @example
     *
     * _.last([1, 2, 3]);
     * // => 3
     *
     * // returns the last two elements
     * _.last([1, 2, 3], 2);
     * // => [2, 3]
     *
     * // returns elements from the end until the callback fails
     * _.last([1, 2, 3], function(num) {
     *   return num > 1;
     * });
     * // => [2, 3]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': false, 'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': true,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true,  'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.pluck(_.last(characters, 'blocked'), 'name');
     * // => ['fred', 'pebbles']
     *
     * // using "_.where" callback shorthand
     * _.last(characters, { 'employer': 'na' });
     * // => [{ 'name': 'pebbles', 'blocked': true, 'employer': 'na' }]
     */
    function last(array, callback, thisArg) {
      var n = 0,
          length = array ? array.length : 0;
  
      if (typeof callback != 'number' && callback != null) {
        var index = length;
        callback = createCallback(callback, thisArg, 3);
        while (index-- && callback(array[index], index, array)) {
          n++;
        }
      } else {
        n = callback;
        if (n == null || thisArg) {
          return array ? array[length - 1] : undefined;
        }
      }
      n = length - n;
      return slice(array,  n > 0 ? n : 0);
    }
  
    /**
     * Gets the index at which the last occurrence of `value` is found using strict
     * equality for comparisons, i.e. `===`. If `fromIndex` is negative, it is used
     * as the offset from the end of the collection.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to search.
     * @param {*} value The value to search for.
     * @param {number} [fromIndex=array.length-1] The index to search from.
     * @returns {number} Returns the index of the matched value or `-1`.
     * @example
     *
     * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2);
     * // => 4
     *
     * // using `fromIndex`
     * _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3);
     * // => 1
     */
    function lastIndexOf(array, value, fromIndex) {
      var index = array ? array.length : 0;
      if (typeof fromIndex == 'number') {
        index = (fromIndex < 0 ? nativeMax(0, index + fromIndex) : nativeMin(fromIndex, index - 1)) + 1;
      }
      while (index--) {
        if (array[index] === value) {
          return index;
        }
      }
      return -1;
    }
  
    /**
     * Creates an array of numbers (positive and/or negative) progressing from
     * `start` up to but not including `end`. If `start` is less than `stop` a
     * zero-length range is created unless a negative `step` is specified.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {number} [start=0] The start of the range.
     * @param {number} end The end of the range.
     * @param {number} [step=1] The value to increment or decrement by.
     * @returns {Array} Returns a new range array.
     * @example
     *
     * _.range(4);
     * // => [0, 1, 2, 3]
     *
     * _.range(1, 5);
     * // => [1, 2, 3, 4]
     *
     * _.range(0, 20, 5);
     * // => [0, 5, 10, 15]
     *
     * _.range(0, -4, -1);
     * // => [0, -1, -2, -3]
     *
     * _.range(1, 4, 0);
     * // => [1, 1, 1]
     *
     * _.range(0);
     * // => []
     */
    function range(start, end, step) {
      start = +start || 0;
      step =  (+step || 1);
  
      if (end == null) {
        end = start;
        start = 0;
      }
      // use `Array(length)` so engines like Chakra and V8 avoid slower modes
      // http://youtu.be/XAqIpGU8ZZk#t=17m25s
      var index = -1,
          length = nativeMax(0, ceil((end - start) / step)),
          result = Array(length);
  
      while (++index < length) {
        result[index] = start;
        start += step;
      }
      return result;
    }
  
    /**
     * The opposite of `_.initial`; this method gets all but the first element or
     * first `n` elements of an array. If a callback function is provided elements
     * at the beginning of the array are excluded from the result as long as the
     * callback returns truey. The callback is bound to `thisArg` and invoked
     * with three arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias drop, tail
     * @category Arrays
     * @param {Array} array The array to query.
     * @param {Function|Object|number|string} [callback=1] The function called
     *  per element or the number of elements to exclude. If a property name or
     *  object is provided it will be used to create a "_.pluck" or "_.where"
     *  style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a slice of `array`.
     * @example
     *
     * _.rest([1, 2, 3]);
     * // => [2, 3]
     *
     * // excludes the first two elements
     * _.rest([1, 2, 3], 2);
     * // => [3]
     *
     * // excludes elements from the beginning until the callback fails
     * _.rest([1, 2, 3], function(num) {
     *   return num < 3;
     * });
     * // => [3]
     *
     * var characters = [
     *   { 'name': 'barney',  'blocked': true,  'employer': 'slate' },
     *   { 'name': 'fred',    'blocked': false,  'employer': 'slate' },
     *   { 'name': 'pebbles', 'blocked': true, 'employer': 'na' }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.pluck(_.rest(characters, 'blocked'), 'name');
     * // => ['fred', 'pebbles']
     *
     * // using "_.where" callback shorthand
     * _.rest(characters, { 'employer': 'slate' });
     * // => [{ 'name': 'pebbles', 'blocked': true, 'employer': 'na' }]
     */
    function rest(array, callback, thisArg) {
      if (typeof callback != 'number' && callback != null) {
        var n = 0,
            index = -1,
            length = array ? array.length : 0;
  
        callback = createCallback(callback, thisArg, 3);
        while (++index < length && callback(array[index], index, array)) {
          n++;
        }
      } else if (callback == null || thisArg) {
        n = 1;
      } else {
        n = callback > 0 ? callback : 0;
      }
      return slice(array, n);
    }
  
    /**
     * Slices `array` from the `start` index up to, but not including, the `end` index.
     *
     * Note: This function is used instead of `Array#slice` to support node lists
     * in IE < 9 and to ensure dense arrays are returned.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to slice.
     * @param {number} [start=0] The start index.
     * @param {number} [end=array.length] The end index.
     * @returns {Array} Returns the new array.
     */
    function slice(array, start, end) {
      var index = -1,
          length = array ? array.length : 0;
  
      if (typeof start == 'undefined') {
        start = 0;
      } else if (start < 0) {
        start = nativeMax(length + start, 0);
      } else if (start > length) {
        start = length;
      }
      if (typeof end == 'undefined') {
        end = length;
      } else if (end < 0) {
        end = nativeMax(length + end, 0);
      } else if (end > length) {
        end = length;
      }
      length = end - start || 0;
  
      var result = Array(length);
      while (++index < length) {
        result[index] = array[start + index];
      }
      return result;
    }
  
    /**
     * Uses a binary search to determine the smallest index at which a value
     * should be inserted into a given sorted array in order to maintain the sort
     * order of the array. If a callback is provided it will be executed for
     * `value` and each element of `array` to compute their sort ranking. The
     * callback is bound to `thisArg` and invoked with one argument; (value).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to inspect.
     * @param {*} value The value to evaluate.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {number} Returns the index at which `value` should be inserted
     *  into `array`.
     * @example
     *
     * _.sortedIndex([20, 30, 50], 40);
     * // => 2
     *
     * var dict = {
     *   'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 }
     * };
     *
     * // using `callback`
     * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
     *   return dict.wordToNumber[word];
     * });
     * // => 2
     *
     * // using `callback` with `thisArg`
     * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
     *   return this.wordToNumber[word];
     * }, dict);
     * // => 2
     *
     * // using "_.pluck" callback shorthand
     * _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
     * // => 2
     */
    function sortedIndex(array, value, callback, thisArg) {
      var low = 0,
          high = array ? array.length : low;
  
      // explicitly reference `identity` for better inlining in Firefox
      callback = callback ? createCallback(callback, thisArg, 1) : identity;
      value = callback(value);
  
      while (low < high) {
        var mid = (low + high) >>> 1;
        (callback(array[mid]) < value)
          ? low = mid + 1
          : high = mid;
      }
      return low;
    }
  
    /**
     * Creates an array of unique values, in order, of the provided arrays using
     * strict equality for comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {...Array} [array] The arrays to inspect.
     * @returns {Array} Returns an array of combined values.
     * @example
     *
     * _.union([1, 2, 3], [5, 2, 1, 4], [2, 1]);
     * // => [1, 2, 3, 5, 4]
     */
    function union() {
      return baseUniq(baseFlatten(arguments, true, true));
    }
  
    /**
     * Creates a duplicate-value-free version of an array using strict equality
     * for comparisons, i.e. `===`. If the array is sorted, providing
     * `true` for `isSorted` will use a faster algorithm. If a callback is provided
     * each element of `array` is passed through the callback before uniqueness
     * is computed. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, array).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias unique
     * @category Arrays
     * @param {Array} array The array to process.
     * @param {boolean} [isSorted=false] A flag to indicate that `array` is sorted.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a duplicate-value-free array.
     * @example
     *
     * _.uniq([1, 2, 1, 3, 1]);
     * // => [1, 2, 3]
     *
     * // using `isSorted`
     * _.uniq([1, 1, 2, 2, 3], true);
     * // => [1, 2, 3]
     *
     * // using `callback`
     * _.uniq(['A', 'b', 'C', 'a', 'B', 'c'], function(letter) { return letter.toLowerCase(); });
     * // => ['A', 'b', 'C']
     *
     * // using `callback` with `thisArg`
     * _.uniq([1, 2.5, 3, 1.5, 2, 3.5], function(num) { return this.floor(num); }, Math);
     * // => [1, 2.5, 3]
     *
     * // using "_.pluck" callback shorthand
     * _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
     * // => [{ 'x': 1 }, { 'x': 2 }]
     */
    function uniq(array, isSorted, callback, thisArg) {
      var type = typeof isSorted;
  
      // juggle arguments
      if (type != 'boolean' && isSorted != null) {
        thisArg = callback;
        callback = isSorted;
        isSorted = false;
  
        // enables use as a callback for functions like `_.map`
        if ((type == 'number' || type == 'string') && thisArg && thisArg[callback] === array) {
          callback = null;
        }
      }
      if (callback != null) {
        callback = createCallback(callback, thisArg, 3);
      }
      return baseUniq(array, isSorted, callback);
    }
  
    /**
     * Creates an array excluding all provided values using strict equality for
     * comparisons, i.e. `===`.
     *
     * @static
     * @memberOf _
     * @category Arrays
     * @param {Array} array The array to filter.
     * @param {...*} [value] The values to exclude.
     * @returns {Array} Returns a new array of filtered values.
     * @example
     *
     * _.without([1, 2, 1, 0, 3, 1, 4], 0, 1);
     * // => [2, 3, 4]
     */
    function without(array) {
      return baseDifference(array, slice(arguments, 1));
    }
  
    /**
     * Creates an array of grouped elements, the first of which contains the
     * first elements of the given arrays, the second of which contains the second
     * elements of the given arrays, and so on. If a zipped value is provided its
     * corresponding unzipped value will be returned.
     *
     * @static
     * @memberOf _
     * @alias unzip
     * @category Arrays
     * @param {...Array} [array] Arrays to process.
     * @returns {Array} Returns a new array of grouped elements.
     * @example
     *
     * _.zip(['fred', 'barney'], [30, 40], [true, false]);
     * // => [['fred', 30, true], ['barney', 40, false]]
     *
     * _.unzip([['fred', 30, true], ['barney', 40, false]]);
     * // => [['fred', 'barney'], [30, 40], [true, false]]
     */
    function zip() {
      var index = -1,
          length = max(pluck(arguments, 'length')),
          result = Array(length < 0 ? 0 : length);
  
      while (++index < length) {
        result[index] = pluck(arguments, index);
      }
      return result;
    }
  
    /**
     * Creates an object composed from arrays of `keys` and `values`. Provide
     * either a single two dimensional array, i.e. `[[key1, value1], [key2, value2]]`
     * or two arrays, one of `keys` and one of corresponding `values`.
     *
     * @static
     * @memberOf _
     * @alias object
     * @category Arrays
     * @param {Array} keys The array of keys.
     * @param {Array} [values=[]] The array of values.
     * @returns {Object} Returns an object composed of the given keys and
     *  corresponding values.
     * @example
     *
     * _.zipObject(['fred', 'barney'], [30, 40]);
     * // => { 'fred': 30, 'barney': 40 }
     */
    function zipObject(keys, values) {
      var index = -1,
          length = keys ? keys.length : 0,
          result = {};
  
      if (!values && length && !isArray(keys[0])) {
        values = [];
      }
      while (++index < length) {
        var key = keys[index];
        if (values) {
          result[key] = values[index];
        } else if (key) {
          result[key[0]] = key[1];
        }
      }
      return result;
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Creates a `lodash` object that wraps `value` with explicit method
     * chaining enabled.
     *
     * @static
     * @memberOf _
     * @category Chaining
     * @param {*} value The value to wrap.
     * @returns {Object} Returns the wrapper object.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36 },
     *   { 'name': 'fred',    'age': 40 },
     *   { 'name': 'pebbles', 'age': 1 }
     * ];
     *
     * var youngest = _.chain(characters)
     *     .sortBy('age')
     *     .map(function(chr) { return chr.name + ' is ' + chr.age; })
     *     .first()
     *     .value();
     * // => 'pebbles is 1'
     */
    function chain(value) {
      value = new lodashWrapper(value);
      value.__chain__ = true;
      return value;
    }
  
    /**
     * This method invokes `interceptor` and returns `value`. The interceptor is
     * bound to `thisArg` and invoked with one argument; (value). The purpose of
     * this method is to "tap into" a method chain in order to perform operations
     * on intermediate results within the chain.
     *
     * @static
     * @memberOf _
     * @category Chaining
     * @param {*} value The value to provide to `interceptor`.
     * @param {Function} interceptor The function to invoke.
     * @param {*} [thisArg] The `this` binding of `interceptor`.
     * @returns {*} Returns `value`.
     * @example
     *
     * _([1, 2, 3, 4])
     *  .tap(function(array) { array.pop(); })
     *  .reverse()
     *  .value();
     * // => [3, 2, 1]
     */
    function tap(value, interceptor) {
      interceptor(value);
      return value;
    }
  
    /**
     * Enables explicit method chaining on the wrapper object.
     *
     * @name chain
     * @memberOf _
     * @category Chaining
     * @returns {*} Returns the wrapper object.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // without explicit chaining
     * _(characters).first();
     * // => { 'name': 'barney', 'age': 36 }
     *
     * // with explicit chaining
     * _(characters).chain()
     *   .first()
     *   .pick('age')
     *   .value();
     * // => { 'age': 36 }
     */
    function wrapperChain() {
      this.__chain__ = true;
      return this;
    }
  
    /**
     * Extracts the wrapped value.
     *
     * @name valueOf
     * @memberOf _
     * @alias value
     * @category Chaining
     * @returns {*} Returns the wrapped value.
     * @example
     *
     * _([1, 2, 3]).valueOf();
     * // => [1, 2, 3]
     */
    function wrapperValueOf() {
      return this.__wrapped__;
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Checks if a given value is present in a collection using strict equality
     * for comparisons, i.e. `===`. If `fromIndex` is negative, it is used as the
     * offset from the end of the collection.
     *
     * @static
     * @memberOf _
     * @alias include
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {*} target The value to check for.
     * @param {number} [fromIndex=0] The index to search from.
     * @returns {boolean} Returns `true` if the `target` element is found, else `false`.
     * @example
     *
     * _.contains([1, 2, 3], 1);
     * // => true
     *
     * _.contains([1, 2, 3], 1, 2);
     * // => false
     *
     * _.contains({ 'name': 'fred', 'age': 40 }, 'fred');
     * // => true
     *
     * _.contains('pebbles', 'eb');
     * // => true
     */
    function contains(collection, target) {
      var indexOf = getIndexOf(),
          length = collection ? collection.length : 0,
          result = false;
      if (length && typeof length == 'number') {
        result = indexOf(collection, target) > -1;
      } else {
        baseEach(collection, function(value) {
          return (result = value === target) && breakIndicator;
        });
      }
      return result;
    }
  
    /**
     * Creates an object composed of keys generated from the results of running
     * each element of `collection` through the callback. The corresponding value
     * of each key is the number of times the key was returned by the callback.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.countBy([4.3, 6.1, 6.4], function(num) { return Math.floor(num); });
     * // => { '4': 1, '6': 2 }
     *
     * _.countBy([4.3, 6.1, 6.4], function(num) { return this.floor(num); }, Math);
     * // => { '4': 1, '6': 2 }
     *
     * _.countBy(['one', 'two', 'three'], 'length');
     * // => { '3': 2, '5': 1 }
     */
    var countBy = createAggregator(function(result, value, key) {
      (hasOwnProperty.call(result, key) ? result[key]++ : result[key] = 1);
    });
  
    /**
     * Checks if the callback returns truey value for **all** elements of a
     * collection. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias all
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if all elements passed the callback check,
     *  else `false`.
     * @example
     *
     * _.every([true, 1, null, 'yes']);
     * // => false
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.every(characters, 'age');
     * // => true
     *
     * // using "_.where" callback shorthand
     * _.every(characters, { 'age': 36 });
     * // => false
     */
    function every(collection, callback, thisArg) {
      var result = true;
  
      callback = createCallback(callback, thisArg, 3);
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (++index < length) {
          if (!(result = !!callback(collection[index], index, collection))) {
            break;
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          return !(result = !!callback(value, index, collection)) && breakIndicator;
        });
      }
      return result;
    }
  
    /**
     * Iterates over elements of a collection, returning an array of all elements
     * the callback returns truey for. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias select
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of elements that passed the callback check.
     * @example
     *
     * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; });
     * // => [2, 4, 6]
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.filter(characters, 'blocked');
     * // => [{ 'name': 'fred', 'age': 40, 'blocked': true }]
     *
     * // using "_.where" callback shorthand
     * _.filter(characters, { 'age': 36 });
     * // => [{ 'name': 'barney', 'age': 36, 'blocked': false }]
     */
    function filter(collection, callback, thisArg) {
      var result = [];
  
      callback = createCallback(callback, thisArg, 3);
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (++index < length) {
          var value = collection[index];
          if (callback(value, index, collection)) {
            result.push(value);
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          if (callback(value, index, collection)) {
            result.push(value);
          }
        });
      }
      return result;
    }
  
    /**
     * Iterates over elements of a collection, returning the first element that
     * the callback returns truey for. The callback is bound to `thisArg` and
     * invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias detect, findWhere
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the found element, else `undefined`.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36, 'blocked': false },
     *   { 'name': 'fred',    'age': 40, 'blocked': true },
     *   { 'name': 'pebbles', 'age': 1,  'blocked': false }
     * ];
     *
     * _.find(characters, function(chr) {
     *   return chr.age < 40;
     * });
     * // => { 'name': 'barney', 'age': 36, 'blocked': false }
     *
     * // using "_.where" callback shorthand
     * _.find(characters, { 'age': 1 });
     * // =>  { 'name': 'pebbles', 'age': 1, 'blocked': false }
     *
     * // using "_.pluck" callback shorthand
     * _.find(characters, 'blocked');
     * // => { 'name': 'fred', 'age': 40, 'blocked': true }
     */
    function find(collection, callback, thisArg) {
      callback = createCallback(callback, thisArg, 3);
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (++index < length) {
          var value = collection[index];
          if (callback(value, index, collection)) {
            return value;
          }
        }
      } else {
        var result;
        baseEach(collection, function(value, index, collection) {
          if (callback(value, index, collection)) {
            result = value;
            return breakIndicator;
          }
        });
        return result;
      }
    }
  
    /**
     * Examines each element in a `collection`, returning the first that
     * has the given properties. When checking `properties`, this method
     * performs a deep comparison between values to determine if they are
     * equivalent to each other.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Object} properties The object of property values to filter by.
     * @returns {*} Returns the found element, else `undefined`.
     * @example
     *
     * var food = [
     *   { 'name': 'apple',  'organic': false, 'type': 'fruit' },
     *   { 'name': 'banana', 'organic': true,  'type': 'fruit' },
     *   { 'name': 'beet',   'organic': false, 'type': 'vegetable' }
     * ];
     *
     * _.findWhere(food, { 'type': 'vegetable' });
     * // => { 'name': 'beet', 'organic': false, 'type': 'vegetable' }
     */
    function findWhere(object, properties) {
      return where(object, properties, true);
    }
  
    /**
     * Iterates over elements of a collection, executing the callback for each
     * element. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection). Callbacks may exit iteration early by
     * explicitly returning `false`.
     *
     * Note: As with other "Collections" methods, objects with a `length` property
     * are iterated like arrays. To avoid this behavior `_.forIn` or `_.forOwn`
     * may be used for object iteration.
     *
     * @static
     * @memberOf _
     * @alias each
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array|Object|string} Returns `collection`.
     * @example
     *
     * _([1, 2, 3]).forEach(function(num) { console.log(num); }).join(',');
     * // => logs each number and returns '1,2,3'
     *
     * _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { console.log(num); });
     * // => logs each number and returns the object (property order is not guaranteed across environments)
     */
    function forEach(collection, callback, thisArg) {
      var index = -1,
          length = collection ? collection.length : 0;
  
      callback = callback && typeof thisArg == 'undefined' ? callback : baseCreateCallback(callback, thisArg, 3);
      if (typeof length == 'number') {
        while (++index < length) {
          if (callback(collection[index], index, collection) === breakIndicator) {
            break;
          }
        }
      } else {
        baseEach(collection, callback);
      }
    }
  
    /**
     * Creates an object composed of keys generated from the results of running
     * each element of a collection through the callback. The corresponding value
     * of each key is an array of the elements responsible for generating the key.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * _.groupBy([4.2, 6.1, 6.4], function(num) { return Math.floor(num); });
     * // => { '4': [4.2], '6': [6.1, 6.4] }
     *
     * _.groupBy([4.2, 6.1, 6.4], function(num) { return this.floor(num); }, Math);
     * // => { '4': [4.2], '6': [6.1, 6.4] }
     *
     * // using "_.pluck" callback shorthand
     * _.groupBy(['one', 'two', 'three'], 'length');
     * // => { '3': ['one', 'two'], '5': ['three'] }
     */
    var groupBy = createAggregator(function(result, value, key) {
      if (hasOwnProperty.call(result, key)) {
        result[key].push(value);
      } else {
        result[key] = [value];
      }
    });
  
    /**
     * Creates an object composed of keys generated from the results of running
     * each element of the collection through the given callback. The corresponding
     * value of each key is the last element responsible for generating the key.
     * The callback is bound to `thisArg` and invoked with three arguments;
     * (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the composed aggregate object.
     * @example
     *
     * var keys = [
     *   { 'dir': 'left', 'code': 97 },
     *   { 'dir': 'right', 'code': 100 }
     * ];
     *
     * _.indexBy(keys, 'dir');
     * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
     *
     * _.indexBy(keys, function(key) { return String.fromCharCode(key.code); });
     * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
     *
     * _.indexBy(characters, function(key) { this.fromCharCode(key.code); }, String);
     * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
     */
    var indexBy = createAggregator(function(result, value, key) {
      result[key] = value;
    });
  
    /**
     * Invokes the method named by `methodName` on each element in the `collection`
     * returning an array of the results of each invoked method. Additional arguments
     * will be provided to each invoked method. If `methodName` is a function it
     * will be invoked for, and `this` bound to, each element in the `collection`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|string} methodName The name of the method to invoke or
     *  the function invoked per iteration.
     * @param {...*} [args] Arguments to invoke the method with.
     * @returns {Array} Returns a new array of the results of each invoked method.
     * @example
     *
     * _.invoke([[5, 1, 7], [3, 2, 1]], 'sort');
     * // => [[1, 5, 7], [1, 2, 3]]
     *
     * _.invoke([123, 456], String.prototype.split, '');
     * // => [['1', '2', '3'], ['4', '5', '6']]
     */
    function invoke(collection, methodName) {
      var index = -1,
          isFunc = typeof methodName == 'function',
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);
  
      if (arguments.length < 3 && typeof length == 'number') {
        while (++index < length) {
          var value = collection[index];
          result[index] = isFunc ? methodName.call(value) : value[methodName]();
        }
      } else {
        var args = slice(arguments, 2);
        baseEach(collection, function(value) {
          result[++index] = (isFunc ? methodName : value[methodName]).apply(value, args);
        });
      }
      return result;
    }
  
    /**
     * Creates an array of values by running each element in the collection
     * through the callback. The callback is bound to `thisArg` and invoked with
     * three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias collect
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of the results of each `callback` execution.
     * @example
     *
     * _.map([1, 2, 3], function(num) { return num * 3; });
     * // => [3, 6, 9]
     *
     * _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(num) { return num * 3; });
     * // => [3, 6, 9] (property order is not guaranteed across environments)
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.map(characters, 'name');
     * // => ['barney', 'fred']
     */
    function map(collection, callback, thisArg) {
      var index = -1,
          length = collection ? collection.length : 0;
  
      callback = createCallback(callback, thisArg, 3);
      if (typeof length == 'number') {
        var result = Array(length);
        while (++index < length) {
          result[index] = callback(collection[index], index, collection);
        }
      } else {
        result = [];
        baseEach(collection, function(value, key, collection) {
          result[++index] = callback(value, key, collection);
        });
      }
      return result;
    }
  
    /**
     * Retrieves the maximum value of a collection. If the collection is empty or
     * falsey `-Infinity` is returned. If a callback is provided it will be executed
     * for each value in the collection to generate the criterion by which the value
     * is ranked. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the maximum value.
     * @example
     *
     * _.max([4, 2, 8, 6]);
     * // => 8
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.max(characters, function(chr) { return chr.age; });
     * // => { 'name': 'fred', 'age': 40 };
     *
     * // using "_.pluck" callback shorthand
     * _.max(characters, 'age');
     * // => { 'name': 'fred', 'age': 40 };
     */
    function max(collection, callback, thisArg) {
      var computed = -Infinity,
          result = computed,
          type = typeof callback;
  
      // enables use as a callback for functions like `_.map`
      if ((type == 'number' || type == 'string') && thisArg && thisArg[callback] === collection) {
        callback = null;
      }
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (callback == null && typeof length == 'number') {
        while (++index < length) {
          var value = collection[index];
          if (value > result) {
            result = value;
          }
        }
      } else {
        callback = createCallback(callback, thisArg, 3);
  
        baseEach(collection, function(value, index, collection) {
          var current = callback(value, index, collection);
          if (current > computed) {
            computed = current;
            result = value;
          }
        });
      }
      return result;
    }
  
    /**
     * Retrieves the minimum value of a collection. If the collection is empty or
     * falsey `Infinity` is returned. If a callback is provided it will be executed
     * for each value in the collection to generate the criterion by which the value
     * is ranked. The callback is bound to `thisArg` and invoked with three
     * arguments; (value, index, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the minimum value.
     * @example
     *
     * _.min([4, 2, 8, 6]);
     * // => 2
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.min(characters, function(chr) { return chr.age; });
     * // => { 'name': 'barney', 'age': 36 };
     *
     * // using "_.pluck" callback shorthand
     * _.min(characters, 'age');
     * // => { 'name': 'barney', 'age': 36 };
     */
    function min(collection, callback, thisArg) {
      var computed = Infinity,
          result = computed,
          type = typeof callback;
  
      // enables use as a callback for functions like `_.map`
      if ((type == 'number' || type == 'string') && thisArg && thisArg[callback] === collection) {
        callback = null;
      }
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (callback == null && typeof length == 'number') {
        while (++index < length) {
          var value = collection[index];
          if (value < result) {
            result = value;
          }
        }
      } else {
        callback = createCallback(callback, thisArg, 3);
  
        baseEach(collection, function(value, index, collection) {
          var current = callback(value, index, collection);
          if (current < computed) {
            computed = current;
            result = value;
          }
        });
      }
      return result;
    }
  
    /**
     * Retrieves the value of a specified property from all elements in the collection.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {string} key The name of the property to pluck.
     * @returns {Array} Returns a new array of property values.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * _.pluck(characters, 'name');
     * // => ['barney', 'fred']
     */
    var pluck = map;
  
    /**
     * Reduces a collection to a value which is the accumulated result of running
     * each element in the collection through the callback, where each successive
     * callback execution consumes the return value of the previous execution. If
     * `accumulator` is not provided the first element of the collection will be
     * used as the initial `accumulator` value. The callback is bound to `thisArg`
     * and invoked with four arguments; (accumulator, value, index|key, collection).
     *
     * @static
     * @memberOf _
     * @alias foldl, inject
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [accumulator] Initial value of the accumulator.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * var sum = _.reduce([1, 2, 3], function(sum, num) {
     *   return sum + num;
     * });
     * // => 6
     *
     * var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, num, key) {
     *   result[key] = num * 3;
     *   return result;
     * }, {});
     * // => { 'a': 3, 'b': 6, 'c': 9 }
     */
    function reduce(collection, callback, accumulator, thisArg) {
      var noaccum = arguments.length < 3;
  
      callback = createCallback(callback, thisArg, 4);
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        if (noaccum && length) {
          accumulator = collection[++index];
        }
        while (++index < length) {
          accumulator = callback(accumulator, collection[index], index, collection);
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          accumulator = noaccum
            ? (noaccum = false, value)
            : callback(accumulator, value, index, collection)
        });
      }
      return accumulator;
    }
  
    /**
     * This method is like `_.reduce` except that it iterates over elements
     * of a `collection` from right to left.
     *
     * @static
     * @memberOf _
     * @alias foldr
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function} [callback=identity] The function called per iteration.
     * @param {*} [accumulator] Initial value of the accumulator.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the accumulated value.
     * @example
     *
     * var list = [[0, 1], [2, 3], [4, 5]];
     * var flat = _.reduceRight(list, function(a, b) { return a.concat(b); }, []);
     * // => [4, 5, 2, 3, 0, 1]
     */
    function reduceRight(collection, callback, accumulator, thisArg) {
      var noaccum = arguments.length < 3;
  
      callback = createCallback(callback, thisArg, 4);
      baseEachRight(collection, function(value, index, collection) {
        accumulator = noaccum
          ? (noaccum = false, value)
          : callback(accumulator, value, index, collection);
      });
      return accumulator;
    }
  
    /**
     * The opposite of `_.filter`; this method returns the elements of a
     * collection that the callback does **not** return truey for.
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of elements that failed the callback check.
     * @example
     *
     * var odds = _.reject([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; });
     * // => [1, 3, 5]
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.reject(characters, 'blocked');
     * // => [{ 'name': 'barney', 'age': 36, 'blocked': false }]
     *
     * // using "_.where" callback shorthand
     * _.reject(characters, { 'age': 36 });
     * // => [{ 'name': 'fred', 'age': 40, 'blocked': true }]
     */
    function reject(collection, callback, thisArg) {
      callback = createCallback(callback, thisArg, 3);
      return filter(collection, function(value, index, collection) {
        return !callback(value, index, collection);
      });
    }
  
    /**
     * Retrieves a random element or `n` random elements from a collection.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to sample.
     * @param {number} [n] The number of elements to sample.
     * @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
     * @returns {*} Returns the random sample(s) of `collection`.
     * @example
     *
     * _.sample([1, 2, 3, 4]);
     * // => 2
     *
     * _.sample([1, 2, 3, 4], 2);
     * // => [3, 1]
     */
    function sample(collection, n, guard) {
      if (collection && typeof collection.length != 'number') {
        collection = values(collection);
      }
      if (n == null || guard) {
        return collection ? collection[baseRandom(0, collection.length - 1)] : undefined;
      }
      var result = shuffle(collection);
      result.length = nativeMin(nativeMax(0, n), result.length);
      return result;
    }
  
    /**
     * Creates an array of shuffled values, using a version of the Fisher-Yates
     * shuffle. See [Wikipedia](http://en.wikipedia.org/wiki/Fisher-Yates_shuffle) for more details.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to shuffle.
     * @returns {Array} Returns a new shuffled collection.
     * @example
     *
     * _.shuffle([1, 2, 3, 4, 5, 6]);
     * // => [4, 1, 6, 3, 5, 2]
     */
    function shuffle(collection) {
      var index = -1,
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);
  
      baseEach(collection, function(value) {
        var rand = baseRandom(0, ++index);
        result[index] = result[rand];
        result[rand] = value;
      });
  
      return result;
    }
  
    /**
     * Gets the size of the `collection` by returning `collection.length` for arrays
     * and array-like objects or the number of own enumerable properties for objects.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to inspect.
     * @returns {number} Returns `collection.length` or number of own enumerable properties.
     * @example
     *
     * _.size([1, 2]);
     * // => 2
     *
     * _.size({ 'one': 1, 'two': 2, 'three': 3 });
     * // => 3
     *
     * _.size('pebbles');
     * // => 7
     */
    function size(collection) {
      var length = collection ? collection.length : 0;
      return typeof length == 'number' ? length : keys(collection).length;
    }
  
    /**
     * Checks if the callback returns a truey value for **any** element of a
     * collection. The function returns as soon as it finds a passing value and
     * does not iterate over the entire collection. The callback is bound to
     * `thisArg` and invoked with three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @alias any
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if any element passed the callback check,
     *  else `false`.
     * @example
     *
     * _.some([null, 0, 'yes', false], Boolean);
     * // => true
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'blocked': false },
     *   { 'name': 'fred',   'age': 40, 'blocked': true }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.some(characters, 'blocked');
     * // => true
     *
     * // using "_.where" callback shorthand
     * _.some(characters, { 'age': 1 });
     * // => false
     */
    function some(collection, callback, thisArg) {
      var result;
  
      callback = createCallback(callback, thisArg, 3);
      var index = -1,
          length = collection ? collection.length : 0;
  
      if (typeof length == 'number') {
        while (++index < length) {
          if ((result = callback(collection[index], index, collection))) {
            break;
          }
        }
      } else {
        baseEach(collection, function(value, index, collection) {
          return (result = callback(value, index, collection)) && breakIndicator;
        });
      }
      return !!result;
    }
  
    /**
     * Creates an array of elements, sorted in ascending order by the results of
     * running each element in a collection through the callback. This method
     * performs a stable sort, that is, it will preserve the original sort order
     * of equal elements. The callback is bound to `thisArg` and invoked with
     * three arguments; (value, index|key, collection).
     *
     * If a property name is provided for `callback` the created "_.pluck" style
     * callback will return the property value of the given element.
     *
     * If an array of property names is provided for `callback` the collection
     * will be sorted by each property value.
     *
     * If an object is provided for `callback` the created "_.where" style callback
     * will return `true` for elements that have the properties of the given object,
     * else `false`.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Array|Function|Object|string} [callback=identity] The function called
     *  per iteration. If a property name or object is provided it will be used
     *  to create a "_.pluck" or "_.where" style callback, respectively.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns a new array of sorted elements.
     * @example
     *
     * _.sortBy([1, 2, 3], function(num) { return Math.sin(num); });
     * // => [3, 1, 2]
     *
     * _.sortBy([1, 2, 3], function(num) { return this.sin(num); }, Math);
     * // => [3, 1, 2]
     *
     * var characters = [
     *   { 'name': 'barney',  'age': 36 },
     *   { 'name': 'fred',    'age': 40 },
     *   { 'name': 'barney',  'age': 26 },
     *   { 'name': 'fred',    'age': 30 }
     * ];
     *
     * // using "_.pluck" callback shorthand
     * _.map(_.sortBy(characters, 'age'), _.values);
     * // => [['barney', 26], ['fred', 30], ['barney', 36], ['fred', 40]]
     *
     * // sorting by multiple properties
     * _.map(_.sortBy(characters, ['name', 'age']), _.values);
     * // = > [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
     */
    function sortBy(collection, callback, thisArg) {
      var index = -1,
          length = collection ? collection.length : 0,
          result = Array(typeof length == 'number' ? length : 0);
  
      callback = createCallback(callback, thisArg, 3);
      baseEach(collection, function(value, key, collection) {
        result[++index] = {
          'criteria': callback(value, key, collection),
          'index': index,
          'value': value
        };
      });
  
      length = result.length;
      result.sort(compareAscending);
      while (length--) {
        result[length] = result[length].value;
      }
      return result;
    }
  
    /**
     * Converts the `collection` to an array.
     *
     * @static
     * @memberOf _
     * @category Collections
     * @param {Array|Object|string} collection The collection to convert.
     * @returns {Array} Returns the new converted array.
     * @example
     *
     * (function() { return _.toArray(arguments).slice(1); })(1, 2, 3, 4);
     * // => [2, 3, 4]
     */
    function toArray(collection) {
      if (isArray(collection)) {
        return slice(collection);
      }
      if (collection && typeof collection.length == 'number') {
        return map(collection);
      }
      return values(collection);
    }
  
    /**
     * Performs a deep comparison between each element in `collection` and the
     * `props` object, returning an array of all elements that have equivalent
     * property values.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Collections
     * @param {Array|Object|string} collection The collection to iterate over.
     * @param {Object} props The object of property values to filter by.
     * @returns {Array} Returns a new array of elements that have the given properties.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36, 'pets': ['hoppy'] },
     *   { 'name': 'fred',   'age': 40, 'pets': ['baby puss', 'dino'] }
     * ];
     *
     * _.where(characters, { 'age': 36 });
     * // => [{ 'name': 'barney', 'age': 36, 'pets': ['hoppy'] }]
     *
     * _.where(characters, { 'pets': ['dino'] });
     * // => [{ 'name': 'fred', 'age': 40, 'pets': ['baby puss', 'dino'] }]
     */
    function where(collection, properties, first) {
      return (first && isEmpty(properties))
        ? undefined
        : (first ? find : filter)(collection, properties);
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Creates a function that executes `func`, with  the `this` binding and
     * arguments of the created function, only after being called `n` times.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {number} n The number of times the function must be called before
     *  `func` is executed.
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var saves = ['profile', 'settings'];
     *
     * var done = _.after(saves.length, function() {
     *   console.log('Done saving!');
     * });
     *
     * _.forEach(saves, function(type) {
     *   asyncSave({ 'type': type, 'complete': done });
     * });
     * // => logs 'Done saving!', after all saves have completed
     */
    function after(n, func) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      return function() {
        if (--n < 1) {
          return func.apply(this, arguments);
        }
      };
    }
  
    /**
     * Creates a function that, when called, invokes `func` with the `this`
     * binding of `thisArg` and prepends any additional `bind` arguments to those
     * provided to the bound function.
     *
     * Note: Unlike native `Function#bind` this method does not set the `length`
     * property of bound functions.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to bind.
     * @param {*} [thisArg] The `this` binding of `func`.
     * @param {...*} [args] Arguments to be partially applied.
     * @returns {Function} Returns the new bound function.
     * @example
     *
     * var func = function(greeting) {
     *   return greeting + ' ' + this.name;
     * };
     *
     * func = _.bind(func, { 'name': 'fred' }, 'hi');
     * func();
     * // => 'hi fred'
     */
    function bind(func, thisArg) {
      if (arguments.length < 3) {
        return createWrapper(func, BIND_FLAG, null, thisArg);
      }
      var arity = func && (func[expando] ? func[expando][2] : func.length),
          partialArgs = slice(arguments, 2);
  
      arity -= partialArgs.length;
      return createWrapper(func, BIND_FLAG | PARTIAL_FLAG, arity, thisArg, partialArgs);
    }
  
    /**
     * Binds methods of an object to the object itself, overwriting the existing
     * method. Method names may be specified as individual arguments or as arrays
     * of method names. If no method names are provided all the function properties
     * of `object` will be bound.
     *
     * Note: This method does not set the `length` property of bound functions.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Object} object The object to bind and assign the bound methods to.
     * @param {...string} [methodName] The object method names to
     *  bind, specified as individual method names or arrays of method names.
     * @returns {Object} Returns `object`.
     * @example
     *
     * var view = {
     *   'label': 'docs',
     *   'onClick': function() { console.log('clicked ' + this.label); }
     * };
     *
     * _.bindAll(view);
     * jQuery('#docs').on('click', view.onClick);
     * // => logs 'clicked docs', when the button is clicked
     */
    function bindAll(object) {
      var funcs = arguments.length > 1 ? baseFlatten(arguments, true, false, 1) : functions(object),
          index = -1,
          length = funcs.length;
  
      while (++index < length) {
        var key = funcs[index];
        object[key] = createWrapper(object[key], BIND_FLAG, null, object);
      }
      return object;
    }
  
    /**
     * Creates a function that is the composition of the provided functions,
     * where each function consumes the return value of the function that follows.
     * For example, composing the functions `f()`, `g()`, and `h()` produces `f(g(h()))`.
     * Each function is executed with the `this` binding of the composed function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {...Function} [func] Functions to compose.
     * @returns {Function} Returns the new composed function.
     * @example
     *
     * var realNameMap = {
     *   'pebbles': 'penelope'
     * };
     *
     * var format = function(name) {
     *   name = realNameMap[name.toLowerCase()] || name;
     *   return name.charAt(0).toUpperCase() + name.slice(1).toLowerCase();
     * };
     *
     * var greet = function(formatted) {
     *   return 'Hiya ' + formatted + '!';
     * };
     *
     * var welcome = _.compose(greet, format);
     * welcome('pebbles');
     * // => 'Hiya Penelope!'
     */
    function compose() {
      var funcs = arguments,
          funcsLength = funcs.length,
          length = funcsLength;
  
      while (length--) {
        if (!isFunction(funcs[length])) {
          throw new TypeError;
        }
      }
      return function() {
        var length = funcsLength - 1,
            result = funcs[length].apply(this, arguments);
  
        while (length--) {
          result = funcs[length].call(this, result);
        }
        return result;
      };
    }
  
    /**
     * Creates a function that will delay the execution of `func` until after
     * `wait` milliseconds have elapsed since the last time it was invoked.
     * Provide an options object to indicate that `func` should be invoked on
     * the leading and/or trailing edge of the `wait` timeout. Subsequent calls
     * to the debounced function will return the result of the last `func` call.
     *
     * Note: If `leading` and `trailing` options are `true` `func` will be called
     * on the trailing edge of the timeout only if the the debounced function is
     * invoked more than once during the `wait` timeout.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to debounce.
     * @param {number} wait The number of milliseconds to delay.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.leading=false] Specify execution on the leading edge of the timeout.
     * @param {number} [options.maxWait] The maximum time `func` is allowed to be delayed before it's called.
     * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout.
     * @returns {Function} Returns the new debounced function.
     * @example
     *
     * // avoid costly calculations while the window size is in flux
     * var lazyLayout = _.debounce(calculateLayout, 150);
     * jQuery(window).on('resize', lazyLayout);
     *
     * // execute `sendMail` when the click event is fired, debouncing subsequent calls
     * jQuery('#postbox').on('click', _.debounce(sendMail, 300, {
     *   'leading': true,
     *   'trailing': false
     * });
     *
     * // ensure `batchLog` is executed once after 1 second of debounced calls
     * var source = new EventSource('/stream');
     * source.addEventListener('message', _.debounce(batchLog, 250, {
     *   'maxWait': 1000
     * }, false);
     */
    function debounce(func, wait, options) {
      var args,
          maxTimeoutId,
          result,
          stamp,
          thisArg,
          timeoutId,
          trailingCall,
          lastCalled = 0,
          maxWait = false,
          trailing = true;
  
      if (!isFunction(func)) {
        throw new TypeError;
      }
      wait = nativeMax(0, wait) || 0;
      if (options === true) {
        var leading = true;
        trailing = false;
      } else if (isObject(options)) {
        leading = options.leading;
        maxWait = 'maxWait' in options && (nativeMax(wait, options.maxWait) || 0);
        trailing = 'trailing' in options ? options.trailing : trailing;
      }
      var delayed = function() {
        var remaining = wait - (now() - stamp);
        if (remaining <= 0) {
          if (maxTimeoutId) {
            clearTimeout(maxTimeoutId);
          }
          var isCalled = trailingCall;
          maxTimeoutId = timeoutId = trailingCall = undefined;
          if (isCalled) {
            lastCalled = now();
            result = func.apply(thisArg, args);
            if (!timeoutId && !maxTimeoutId) {
              args = thisArg = null;
            }
          }
        } else {
          timeoutId = setTimeout(delayed, remaining);
        }
      };
  
      var maxDelayed = function() {
        if (timeoutId) {
          clearTimeout(timeoutId);
        }
        maxTimeoutId = timeoutId = trailingCall = undefined;
        if (trailing || (maxWait !== wait)) {
          lastCalled = now();
          result = func.apply(thisArg, args);
          if (!timeoutId && !maxTimeoutId) {
            args = thisArg = null;
          }
        }
      };
  
      return function() {
        args = arguments;
        stamp = now();
        thisArg = this;
        trailingCall = trailing && (timeoutId || !leading);
  
        if (maxWait === false) {
          var leadingCall = leading && !timeoutId;
        } else {
          if (!maxTimeoutId && !leading) {
            lastCalled = stamp;
          }
          var remaining = maxWait - (stamp - lastCalled),
              isCalled = remaining <= 0;
  
          if (isCalled) {
            if (maxTimeoutId) {
              maxTimeoutId = clearTimeout(maxTimeoutId);
            }
            lastCalled = stamp;
            result = func.apply(thisArg, args);
          }
          else if (!maxTimeoutId) {
            maxTimeoutId = setTimeout(maxDelayed, remaining);
          }
        }
        if (isCalled && timeoutId) {
          timeoutId = clearTimeout(timeoutId);
        }
        else if (!timeoutId && wait !== maxWait) {
          timeoutId = setTimeout(delayed, wait);
        }
        if (leadingCall) {
          isCalled = true;
          result = func.apply(thisArg, args);
        }
        if (isCalled && !timeoutId && !maxTimeoutId) {
          args = thisArg = null;
        }
        return result;
      };
    }
  
    /**
     * Defers executing the `func` function until the current call stack has cleared.
     * Additional arguments will be provided to `func` when it is invoked.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to defer.
     * @param {...*} [args] Arguments to invoke the function with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.defer(function(text) { console.log(text); }, 'deferred');
     * // logs 'deferred' after one or more milliseconds
     */
    function defer(func) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      var args = slice(arguments, 1);
      return setTimeout(function() { func.apply(undefined, args); }, 1);
    }
  
    /**
     * Executes the `func` function after `wait` milliseconds. Additional arguments
     * will be provided to `func` when it is invoked.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to delay.
     * @param {number} wait The number of milliseconds to delay execution.
     * @param {...*} [args] Arguments to invoke the function with.
     * @returns {number} Returns the timer id.
     * @example
     *
     * _.delay(function(text) { console.log(text); }, 1000, 'later');
     * // => logs 'later' after one second
     */
    function delay(func, wait) {
      if (!isFunction(func)) {
        throw new TypeError;
      }
      var args = slice(arguments, 2);
      return setTimeout(function() { func.apply(undefined, args); }, wait);
    }
  
    /**
     * Creates a function that memoizes the result of `func`. If `resolver` is
     * provided it will be used to determine the cache key for storing the result
     * based on the arguments provided to the memoized function. By default, the
     * first argument provided to the memoized function is used as the cache key.
     * The `func` is executed with the `this` binding of the memoized function.
     * The result cache is exposed as the `cache` property on the memoized function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to have its output memoized.
     * @param {Function} [resolver] A function used to resolve the cache key.
     * @returns {Function} Returns the new memoizing function.
     * @example
     *
     * var fibonacci = _.memoize(function(n) {
     *   return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2);
     * });
     *
     * fibonacci(9)
     * // => 34
     *
     * var data = {
     *   'fred': { 'name': 'fred', 'age': 40 },
     *   'pebbles': { 'name': 'pebbles', 'age': 1 }
     * };
     *
     * // modifying the result cache
     * var get = _.memoize(function(name) { return data[name]; }, _.identity);
     * get('pebbles');
     * // => { 'name': 'pebbles', 'age': 1 }
     *
     * get.cache.pebbles.name = 'penelope';
     * get('pebbles');
     * // => { 'name': 'penelope', 'age': 1 }
     */
    function memoize(func, resolver) {
      var cache = {};
      return function() {
        var key = resolver ? resolver.apply(this, arguments) : '_' + arguments[0];
        return hasOwnProperty.call(cache, key)
          ? cache[key]
          : (cache[key] = func.apply(this, arguments));
      };
    }
  
    /**
     * Creates a function that is restricted to execute `func` once. Repeat calls to
     * the function will return the value of the first call. The `func` is executed
     * with the `this` binding of the created function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to restrict.
     * @returns {Function} Returns the new restricted function.
     * @example
     *
     * var initialize = _.once(createApplication);
     * initialize();
     * initialize();
     * // `initialize` executes `createApplication` once
     */
    function once(func) {
      var ran,
          result;
  
      if (!isFunction(func)) {
        throw new TypeError;
      }
      return function() {
        if (ran) {
          return result;
        }
        ran = true;
        result = func.apply(this, arguments);
  
        // clear the `func` variable so the function may be garbage collected
        func = null;
        return result;
      };
    }
  
    /**
     * Creates a function that, when called, invokes `func` with any additional
     * `partial` arguments prepended to those provided to the new function. This
     * method is similar to `_.bind` except it does **not** alter the `this` binding.
     *
     * Note: This method does not set the `length` property of partially applied
     * functions.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to partially apply arguments to.
     * @param {...*} [args] Arguments to be partially applied.
     * @returns {Function} Returns the new partially applied function.
     * @example
     *
     * var greet = function(greeting, name) { return greeting + ' ' + name; };
     * var hi = _.partial(greet, 'hi');
     * hi('fred');
     * // => 'hi fred'
     */
    function partial(func) {
      var arity = func && (func[expando] ? func[expando][2] : func.length),
          partialArgs = slice(arguments, 1);
  
      arity -= partialArgs.length;
      return createWrapper(func, PARTIAL_FLAG, arity, null, partialArgs);
    }
  
    /**
     * Creates a function that, when executed, will only call the `func` function
     * at most once per every `wait` milliseconds. Provide an options object to
     * indicate that `func` should be invoked on the leading and/or trailing edge
     * of the `wait` timeout. Subsequent calls to the throttled function will
     * return the result of the last `func` call.
     *
     * Note: If `leading` and `trailing` options are `true` `func` will be called
     * on the trailing edge of the timeout only if the the throttled function is
     * invoked more than once during the `wait` timeout.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {Function} func The function to throttle.
     * @param {number} wait The number of milliseconds to throttle executions to.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.leading=true] Specify execution on the leading edge of the timeout.
     * @param {boolean} [options.trailing=true] Specify execution on the trailing edge of the timeout.
     * @returns {Function} Returns the new throttled function.
     * @example
     *
     * // avoid excessively updating the position while scrolling
     * var throttled = _.throttle(updatePosition, 100);
     * jQuery(window).on('scroll', throttled);
     *
     * // execute `renewToken` when the click event is fired, but not more than once every 5 minutes
     * jQuery('.interactive').on('click', _.throttle(renewToken, 300000, {
     *   'trailing': false
     * }));
     */
    function throttle(func, wait, options) {
      var leading = true,
          trailing = true;
  
      if (!isFunction(func)) {
        throw new TypeError;
      }
      if (options === false) {
        leading = false;
      } else if (isObject(options)) {
        leading = 'leading' in options ? options.leading : leading;
        trailing = 'trailing' in options ? options.trailing : trailing;
      }
      options = {};
      options.leading = leading;
      options.maxWait = wait;
      options.trailing = trailing;
  
      return debounce(func, wait, options);
    }
  
    /**
     * Creates a function that provides `value` to the wrapper function as its
     * first argument. Additional arguments provided to the function are appended
     * to those provided to the wrapper function. The wrapper is executed with
     * the `this` binding of the created function.
     *
     * @static
     * @memberOf _
     * @category Functions
     * @param {*} value The value to wrap.
     * @param {Function} wrapper The wrapper function.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var p = _.wrap(_.escape, function(func, text) {
     *   return '<p>' + func(text) + '</p>';
     * });
     *
     * p('fred, barney, & pebbles');
     * // => '<p>fred, barney, &amp; pebbles</p>'
     */
    function wrap(value, wrapper) {
      return createWrapper(wrapper, PARTIAL_FLAG, null, null, [value]);
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Assigns own enumerable properties of source object(s) to the destination
     * object. Subsequent sources will overwrite property assignments of previous
     * sources. If a callback is provided it will be executed to produce the
     * assigned values. The callback is bound to `thisArg` and invoked with two
     * arguments; (objectValue, sourceValue).
     *
     * @static
     * @memberOf _
     * @alias extend
     * @category Objects
     * @param {Object} object The destination object.
     * @param {...Object} [source] The source objects.
     * @param {Function} [callback] The function to customize assigning values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns the destination object.
     * @example
     *
     * _.assign({ 'name': 'fred' }, { 'employer': 'slate' });
     * // => { 'name': 'fred', 'employer': 'slate' }
     *
     * var defaults = _.partialRight(_.assign, function(a, b) {
     *   return typeof a == 'undefined' ? b : a;
     * });
     *
     * defaults({ 'name': 'barney' }, { 'name': 'fred', 'employer': 'slate' });
     * // => { 'name': 'barney', 'employer': 'slate' }
     */
    function assign(object, source, guard) {
      if (!object) {
        return object;
      }
      var args = arguments,
          argsIndex = 0,
          argsLength = args.length,
          type = typeof guard;
  
      if ((type == 'number' || type == 'string') && args[3] && args[3][guard] === source) {
        argsLength = 2;
      }
      while (++argsIndex < argsLength) {
        source = args[argsIndex];
        if (source) {
          for (var key in source) {
            object[key] = source[key];
          }
        }
      }
      return object;
    }
  
    /**
     * Creates a clone of `value`. If `isDeep` is `true` nested objects will also
     * be cloned, otherwise they will be assigned by reference. If a callback
     * is provided it will be executed to produce the cloned values. If the
     * callback returns `undefined` cloning will be handled by the method instead.
     * The callback is bound to `thisArg` and invoked with one argument; (value).
     *
     * Note: This method is loosely based on the structured clone algorithm. Functions
     * and DOM nodes are **not** cloned. The enumerable properties of `arguments` objects and
     * objects created by constructors other than `Object` are cloned to plain `Object` objects.
     * See the [HTML5 specification](http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm)
     * for more details.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to clone.
     * @param {boolean} [isDeep=false] Specify a deep clone.
     * @param {Function} [callback] The function to customize cloning values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {*} Returns the cloned value.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * var shallow = _.clone(characters);
     * shallow[0] === characters[0];
     * // => true
     *
     * var deep = _.clone(characters, true);
     * deep[0] === characters[0];
     * // => false
     *
     * _.mixin({
     *   'clone': _.partialRight(_.clone, function(value) {
     *     return _.isElement(value) ? value.cloneNode(false) : undefined;
     *   })
     * });
     *
     * var clone = _.clone(document.body);
     * clone.childNodes.length;
     * // => 0
     */
    function clone(value) {
      return isObject(value)
        ? (isArray(value) ? slice(value) : assign({}, value))
        : value;
    }
  
    /**
     * Assigns own enumerable properties of source object(s) to the destination
     * object for all destination properties that resolve to `undefined`. Once a
     * property is set, additional defaults of the same property will be ignored.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The destination object.
     * @param {...Object} [source] The source objects.
     * @param- {Object} [guard] Enables use as a callback for functions like `_.reduce`.
     * @returns {Object} Returns the destination object.
     * @example
     *
     * _.defaults({ 'name': 'barney' }, { 'name': 'fred', 'employer': 'slate' });
     * // => { 'name': 'barney', 'employer': 'slate' }
     */
    function defaults(object, source, guard) {
      if (!object) {
        return object;
      }
      var args = arguments,
          argsIndex = 0,
          argsLength = args.length,
          type = typeof guard;
  
      if ((type == 'number' || type == 'string') && args[3] && args[3][guard] === source) {
        argsLength = 2;
      }
      while (++argsIndex < argsLength) {
        source = args[argsIndex];
        if (source) {
          for (var key in source) {
            if (typeof object[key] == 'undefined') {
              object[key] = source[key];
            }
          }
        }
      }
      return object;
    }
  
    /**
     * Creates a sorted array of property names of all enumerable properties,
     * own and inherited, of `object` that have function values.
     *
     * @static
     * @memberOf _
     * @alias methods
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names that have function values.
     * @example
     *
     * _.functions(_);
     * // => ['all', 'any', 'bind', 'bindAll', 'clone', 'compact', 'compose', ...]
     */
    function functions(object) {
      var result = [];
      baseForIn(object, function(value, key) {
        if (isFunction(value)) {
          result.push(key);
        }
      });
      return result.sort();
    }
  
    /**
     * Checks if the specified property name exists as a direct property of `object`,
     * instead of an inherited property.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @param {string} key The name of the property to check.
     * @returns {boolean} Returns `true` if key is a direct property, else `false`.
     * @example
     *
     * _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b');
     * // => true
     */
    function has(object, key) {
      return object ? hasOwnProperty.call(object, key) : false;
    }
  
    /**
     * Creates an object composed of the inverted keys and values of the given
     * object. If the given object contains duplicate values, subsequent values
     * will overwrite property assignments of previous values unless `multiValue`
     * is `true`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to invert.
     * @param {boolean} [multiValue=false] Allow multiple values per key.
     * @returns {Object} Returns the created inverted object.
     * @example
     *
     * _.invert({ 'first': 'fred', 'second': 'barney' });
     * // => { 'fred': 'first', 'barney': 'second' }
     *
     * // without `multiValue`
     * _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' });
     * // => { 'fred': 'third', 'barney': 'second' }
     *
     * // with `multiValue`
     * _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' }, true);
     * // => { 'fred': ['first', 'third'], 'barney': ['second'] }
     */
    function invert(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = {};
  
      while (++index < length) {
        var key = props[index];
        result[object[key]] = key;
      }
      return result;
    }
  
    /**
     * Checks if `value` is an array.
     *
     * @static
     * @memberOf _
     * @type Function
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an array, else `false`.
     * @example
     *
     * (function() { return _.isArray(arguments); })();
     * // => false
     *
     * _.isArray([1, 2, 3]);
     * // => true
     */
    var isArray = nativeIsArray || function(value) {
      return value && typeof value == 'object' && typeof value.length == 'number' &&
        toString.call(value) == arrayClass || false;
    };
  
    /**
     * Checks if `value` is a boolean value.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a boolean value, else `false`.
     * @example
     *
     * _.isBoolean(null);
     * // => false
     */
    function isBoolean(value) {
      return value === true || value === false ||
        value && typeof value == 'object' && toString.call(value) == boolClass || false;
    }
  
    /**
     * Checks if `value` is a date.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a date, else `false`.
     * @example
     *
     * _.isDate(new Date);
     * // => true
     */
    function isDate(value) {
      return value && typeof value == 'object' && toString.call(value) == dateClass || false;
    }
  
    /**
     * Checks if `value` is a DOM element.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a DOM element, else `false`.
     * @example
     *
     * _.isElement(document.body);
     * // => true
     */
    function isElement(value) {
      return value && value.nodeType === 1 || false;
    }
  
    /**
     * Checks if `value` is empty. Arrays, strings, or `arguments` objects with a
     * length of `0` and objects with no own enumerable properties are considered
     * "empty".
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Array|Object|string} value The value to inspect.
     * @returns {boolean} Returns `true` if the `value` is empty, else `false`.
     * @example
     *
     * _.isEmpty([1, 2, 3]);
     * // => false
     *
     * _.isEmpty({});
     * // => true
     *
     * _.isEmpty('');
     * // => true
     */
    function isEmpty(value) {
      if (!value) {
        return true;
      }
      if (isArray(value) || isString(value)) {
        return !value.length;
      }
      for (var key in value) {
        if (hasOwnProperty.call(value, key)) {
          return false;
        }
      }
      return true;
    }
  
    /**
     * Performs a deep comparison between two values to determine if they are
     * equivalent to each other. If a callback is provided it will be executed
     * to compare values. If the callback returns `undefined` comparisons will
     * be handled by the method instead. The callback is bound to `thisArg` and
     * invoked with two arguments; (a, b).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} a The value to compare.
     * @param {*} b The other value to compare.
     * @param {Function} [callback] The function to customize comparing values.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
     * @example
     *
     * var object = { 'name': 'fred' };
     * var copy = { 'name': 'fred' };
     *
     * object == copy;
     * // => false
     *
     * _.isEqual(object, copy);
     * // => true
     *
     * var words = ['hello', 'goodbye'];
     * var otherWords = ['hi', 'goodbye'];
     *
     * _.isEqual(words, otherWords, function(a, b) {
     *   var reGreet = /^(?:hello|hi)$/i,
     *       aGreet = _.isString(a) && reGreet.test(a),
     *       bGreet = _.isString(b) && reGreet.test(b);
     *
     *   return (aGreet || bGreet) ? (aGreet == bGreet) : undefined;
     * });
     * // => true
     */
    function isEqual(a, b) {
      return baseIsEqual(a, b);
    }
  
    /**
     * Checks if `value` is, or can be coerced to, a finite number.
     *
     * Note: This method is not the same as native `isFinite` which will return
     * `true` for booleans and empty strings. See the [ES5 spec](http://es5.github.io/#x15.1.2.5)
     * for more details.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is finite, else `false`.
     * @example
     *
     * _.isFinite(-101);
     * // => true
     *
     * _.isFinite('10');
     * // => true
     *
     * _.isFinite(true);
     * // => false
     *
     * _.isFinite('');
     * // => false
     *
     * _.isFinite(Infinity);
     * // => false
     */
    function isFinite(value) {
      return nativeIsFinite(value) && !nativeIsNaN(parseFloat(value));
    }
  
    /**
     * Checks if `value` is a function.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a function, else `false`.
     * @example
     *
     * _.isFunction(_);
     * // => true
     */
    function isFunction(value) {
      return typeof value == 'function';
    }
    // fallback for older versions of Chrome and Safari
    if (isFunction(/x/)) {
      isFunction = function(value) {
        return typeof value == 'function' && toString.call(value) == funcClass;
      };
    }
  
    /**
     * Checks if `value` is the language type of Object.
     * (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is an object, else `false`.
     * @example
     *
     * _.isObject({});
     * // => true
     *
     * _.isObject([1, 2, 3]);
     * // => true
     *
     * _.isObject(1);
     * // => false
     */
    function isObject(value) {
      // check if the value is the ECMAScript language type of Object
      // http://es5.github.io/#x8
      // and avoid a V8 bug
      // http://code.google.com/p/v8/issues/detail?id=2291
      var type = typeof value;
      return value && (type == 'function' || type == 'object') || false;
    }
  
    /**
     * Checks if `value` is `NaN`.
     *
     * Note: This method is not the same as native `isNaN` which will return `true`
     * for `undefined` and other non-numeric values. See the [ES5 spec](http://es5.github.io/#x15.1.2.4)
     * for more details.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `NaN`, else `false`.
     * @example
     *
     * _.isNaN(NaN);
     * // => true
     *
     * _.isNaN(new Number(NaN));
     * // => true
     *
     * isNaN(undefined);
     * // => true
     *
     * _.isNaN(undefined);
     * // => false
     */
    function isNaN(value) {
      // `NaN` as a primitive is the only value that is not equal to itself
      // (perform the [[Class]] check first to avoid errors with some host objects in IE)
      return isNumber(value) && value != +value;
    }
  
    /**
     * Checks if `value` is `null`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `null`, else `false`.
     * @example
     *
     * _.isNull(null);
     * // => true
     *
     * _.isNull(undefined);
     * // => false
     */
    function isNull(value) {
      return value === null;
    }
  
    /**
     * Checks if `value` is a number.
     *
     * Note: `NaN` is considered a number. See the [ES5 spec](http://es5.github.io/#x8.5)
     * for more details.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a number, else `false`.
     * @example
     *
     * _.isNumber(8.4 * 5);
     * // => true
     */
    function isNumber(value) {
      var type = typeof value;
      return type == 'number' ||
        value && type == 'object' && toString.call(value) == numberClass || false;
    }
  
    /**
     * Checks if `value` is a regular expression.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a regular expression, else `false`.
     * @example
     *
     * _.isRegExp(/fred/);
     * // => true
     */
    function isRegExp(value) {
      var type = typeof value;
      return value && (type == 'function' || type == 'object') &&
        toString.call(value) == regexpClass || false;
    }
  
    /**
     * Checks if `value` is a string.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is a string, else `false`.
     * @example
     *
     * _.isString('fred');
     * // => true
     */
    function isString(value) {
      return typeof value == 'string' ||
        value && typeof value == 'object' && toString.call(value) == stringClass || false;
    }
  
    /**
     * Checks if `value` is `undefined`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {*} value The value to check.
     * @returns {boolean} Returns `true` if the `value` is `undefined`, else `false`.
     * @example
     *
     * _.isUndefined(void 0);
     * // => true
     */
    function isUndefined(value) {
      return typeof value == 'undefined';
    }
  
    /**
     * Creates an array composed of the own enumerable property names of an object.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property names.
     * @example
     *
     * _.keys({ 'one': 1, 'two': 2, 'three': 3 });
     * // => ['one', 'two', 'three'] (property order is not guaranteed across environments)
     */
    var keys = !nativeKeys ? shimKeys : function(object) {
      if (!isObject(object)) {
        return [];
      }
      return nativeKeys(object);
    };
  
    /**
     * Creates a shallow clone of `object` excluding the specified properties.
     * Property names may be specified as individual arguments or as arrays of
     * property names. If a callback is provided it will be executed for each
     * property of `object` omitting the properties the callback returns truey
     * for. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, key, object).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The source object.
     * @param {Function|...string|string[]} [callback] The function called per
     *  iteration or property names to omit, specified as individual property
     *  names or arrays of property names.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns an object without the omitted properties.
     * @example
     *
     * _.omit({ 'name': 'fred', 'age': 40 }, 'age');
     * // => { 'name': 'fred' }
     *
     * _.omit({ 'name': 'fred', 'age': 40 }, function(value) {
     *   return typeof value == 'number';
     * });
     * // => { 'name': 'fred' }
     */
    function omit(object, guard) {
      var args = arguments,
          result = {},
          type = typeof guard;
  
      if ((type == 'number' || type == 'string') && args[2] && args[2][guard] === object) {
        args = slice(args);
        splice.call(args, 1, 2);
      }
      var omitProps = baseFlatten(args, true, false, 1),
          length = omitProps.length;
  
      while (length--) {
        omitProps[length] = String(omitProps[length]);
      }
      var props = [];
      baseForIn(object, function(value, key) {
        props.push(key);
      });
  
      var index = -1;
      props = baseDifference(props, omitProps);
      length = props.length;
  
      while (++index < length) {
        var key = props[index];
        result[key] = object[key];
      }
      return result;
    }
  
    /**
     * Creates a two dimensional array of an object's key-value pairs,
     * i.e. `[[key1, value1], [key2, value2]]`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns new array of key-value pairs.
     * @example
     *
     * _.pairs({ 'barney': 36, 'fred': 40 });
     * // => [['barney', 36], ['fred', 40]] (property order is not guaranteed across environments)
     */
    function pairs(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = Array(length);
  
      while (++index < length) {
        var key = props[index];
        result[index] = [key, object[key]];
      }
      return result;
    }
  
    /**
     * Creates a shallow clone of `object` composed of the specified properties.
     * Property names may be specified as individual arguments or as arrays of
     * property names. If a callback is provided it will be executed for each
     * property of `object` picking the properties the callback returns truey
     * for. The callback is bound to `thisArg` and invoked with three arguments;
     * (value, key, object).
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The source object.
     * @param {Function|...string|string[]} [callback] The function called per
     *  iteration or property names to pick, specified as individual property
     *  names or arrays of property names.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Object} Returns an object composed of the picked properties.
     * @example
     *
     * _.pick({ 'name': 'fred', '_userid': 'fred1' }, 'name');
     * // => { 'name': 'fred' }
     *
     * _.pick({ 'name': 'fred', '_userid': 'fred1' }, function(value, key) {
     *   return key.charAt(0) != '_';
     * });
     * // => { 'name': 'fred' }
     */
    function pick(object, guard) {
      var args = arguments,
          type = typeof guard;
  
      if ((type == 'number' || type == 'string') && args[2] && args[2][guard] === object) {
        args = slice(args);
        splice.call(args, 1, 2);
      }
      var index = -1,
          props = baseFlatten(args, true, false, 1),
          length = props.length,
          result = {};
  
      while (++index < length) {
        var key = props[index];
        if (key in object) {
          result[key] = object[key];
        }
      }
      return result;
    }
  
    /**
     * Creates an array composed of the own enumerable property values of `object`.
     *
     * @static
     * @memberOf _
     * @category Objects
     * @param {Object} object The object to inspect.
     * @returns {Array} Returns an array of property values.
     * @example
     *
     * _.values({ 'one': 1, 'two': 2, 'three': 3 });
     * // => [1, 2, 3] (property order is not guaranteed across environments)
     */
    function values(object) {
      var index = -1,
          props = keys(object),
          length = props.length,
          result = Array(length);
  
      while (++index < length) {
        result[index] = object[props[index]];
      }
      return result;
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Converts the characters "&", "<", ">", '"', and "'" in `string` to
     * their corresponding HTML entities.
     *
     * Note: No other characters are escaped. To escape additional characters
     * use a third-party library like [_he_](http://mths.be/he).
     *
     * When working with HTML you should always quote attribute values to reduce
     * XSS vectors. See [Ryan Grove's article](http://wonko.com/post/html-escaping)
     * for more details.
     *
     * @static
     * @memberOf _
     * @category Strings
     * @param {string} string The string to escape.
     * @returns {string} Returns the escaped string.
     * @example
     *
     * _.escape('fred, barney, & pebbles');
     * // => 'fred, barney, &amp; pebbles'
     */
    function escape(string) {
      return string == null ? '' : String(string).replace(reUnescapedHtml, escapeHtmlChar);
    }
  
    /**
     * A micro-templating method that handles arbitrary delimiters, preserves
     * whitespace, and correctly escapes quotes within interpolated code.
     *
     * Note: In the development build, `_.template` utilizes sourceURLs for easier
     * debugging. See [HTML5 Rocks' article on sourcemaps](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)
     * for more details.
     *
     * For more information on precompiling templates see
     * [Lo-Dash's custom builds documentation](http://lodash.com/custom-builds).
     *
     * For more information on Chrome extension sandboxes see
     * [Chrome's extensions documentation](http://developer.chrome.com/stable/extensions/sandboxingEval.html).
     *
     * @static
     * @memberOf _
     * @category Strings
     * @param {string} text The template text.
     * @param {Object} [data] The data object used to populate the text.
     * @param {Object} [options] The options object.
     * @param {RegExp} [options.escape] The "escape" delimiter.
     * @param {RegExp} [options.evaluate] The "evaluate" delimiter.
     * @param {Object} [options.imports] An object to import into the template as local variables.
     * @param {RegExp} [options.interpolate] The "interpolate" delimiter.
     * @param {string} [options.sourceURL] The sourceURL of the template's compiled source.
     * @param {string} [options.variable] The data object variable name.
     * @returns {Function|string} Returns a compiled function when no `data` object
     *  is given, else it returns the interpolated text.
     * @example
     *
     * // using the "interpolate" delimiter to create a compiled template
     * var compiled = _.template('hello <%= name %>');
     * compiled({ 'name': 'fred' });
     * // => 'hello fred'
     *
     * // using the "escape" delimiter to escape HTML in data property values
     * _.template('<b><%- value %></b>', { 'value': '<script>' });
     * // => '<b>&lt;script&gt;</b>'
     *
     * // using the "evaluate" delimiter to generate HTML
     * var list = '<% _.forEach(people, function(name) { %><li><%- name %></li><% }); %>';
     * _.template(list, { 'people': ['fred', 'barney'] });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // using the ES6 delimiter as an alternative to the default "interpolate" delimiter
     * _.template('hello ${ name }', { 'name': 'pebbles' });
     * // => 'hello pebbles'
     *
     * // using the internal `print` function in "evaluate" delimiters
     * _.template('<% print("hello " + name); %>!', { 'name': 'barney' });
     * // => 'hello barney!'
     *
     * // using a custom template delimiters
     * _.templateSettings = {
     *   'interpolate': /{{([\s\S]+?)}}/g
     * };
     *
     * _.template('hello {{ name }}!', { 'name': 'mustache' });
     * // => 'hello mustache!'
     *
     * // using the `imports` option to import jQuery
     * var list = '<% jq.each(people, function(name) { %><li><%- name %></li><% }); %>';
     * _.template(list, { 'people': ['fred', 'barney'] }, { 'imports': { 'jq': jQuery } });
     * // => '<li>fred</li><li>barney</li>'
     *
     * // using the `sourceURL` option to specify a custom sourceURL for the template
     * var compiled = _.template('hello <%= name %>', null, { 'sourceURL': '/basic/greeting.jst' });
     * compiled(data);
     * // => find the source of "greeting.jst" under the Sources tab or Resources panel of the web inspector
     *
     * // using the `variable` option to ensure a with-statement isn't used in the compiled template
     * var compiled = _.template('hi <%= data.name %>!', null, { 'variable': 'data' });
     * compiled.source;
     * // => function(data) {
     *   var __t, __p = '', __e = _.escape;
     *   __p += 'hi ' + ((__t = ( data.name )) == null ? '' : __t) + '!';
     *   return __p;
     * }
     *
     * // using the `source` property to inline compiled templates for meaningful
     * // line numbers in error messages and a stack trace
     * fs.writeFileSync(path.join(cwd, 'jst.js'), '\
     *   var JST = {\
     *     "main": ' + _.template(mainText).source + '\
     *   };\
     * ');
     */
    function template(text, data, options) {
      var _ = lodash,
          settings = _.templateSettings;
  
      text = String(text || '');
      options = defaults({}, options, settings);
  
      var index = 0,
          source = "__p += '",
          variable = options.variable;
  
      var reDelimiters = RegExp(
        (options.escape || reNoMatch).source + '|' +
        (options.interpolate || reNoMatch).source + '|' +
        (options.evaluate || reNoMatch).source + '|$'
      , 'g');
  
      text.replace(reDelimiters, function(match, escapeValue, interpolateValue, evaluateValue, offset) {
        source += text.slice(index, offset).replace(reUnescapedString, escapeStringChar);
        if (escapeValue) {
          source += "' +\n_.escape(" + escapeValue + ") +\n'";
        }
        if (evaluateValue) {
          source += "';\n" + evaluateValue + ";\n__p += '";
        }
        if (interpolateValue) {
          source += "' +\n((__t = (" + interpolateValue + ")) == null ? '' : __t) +\n'";
        }
        index = offset + match.length;
        return match;
      });
  
      source += "';\n";
      if (!variable) {
        variable = 'obj';
        source = 'with (' + variable + ' || {}) {\n' + source + '\n}\n';
      }
      source = 'function(' + variable + ') {\n' +
        "var __t, __p = '', __j = Array.prototype.join;\n" +
        "function print() { __p += __j.call(arguments, '') }\n" +
        source +
        'return __p\n}';
  
      try {
        var result = Function('_', 'return ' + source)(_);
      } catch(e) {
        e.source = source;
        throw e;
      }
      if (data) {
        return result(data);
      }
      result.source = source;
      return result;
    }
  
    /**
     * The inverse of `_.escape`; this method converts the HTML entities
     * `&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to their
     * corresponding characters.
     *
     * Note: No other HTML entities are unescaped. To unescape additional HTML
     * entities use a third-party library like [_he_](http://mths.be/he).
     *
     * @static
     * @memberOf _
     * @category Strings
     * @param {string} string The string to unescape.
     * @returns {string} Returns the unescaped string.
     * @example
     *
     * _.unescape('fred, barney &amp; pebbles');
     * // => 'fred, barney & pebbles'
     */
    function unescape(string) {
      if (string == null) {
        return '';
      }
      string = String(string);
      return string.indexOf(';') < 0 ? string : string.replace(reEscapedHtml, unescapeHtmlChar);
    }
  
    /*--------------------------------------------------------------------------*/
  
    /**
     * Produces a callback bound to an optional `thisArg`. If `func` is a property
     * name the created callback will return the property value for a given element.
     * If `func` is an object the created callback will return `true` for elements
     * that contain the equivalent object properties, otherwise it will return `false`.
     *
     * @static
     * @memberOf _
     * @alias callback
     * @category Utilities
     * @param {*} [func=identity] The value to convert to a callback.
     * @param {*} [thisArg] The `this` binding of the created callback.
     * @param {number} [argCount] The number of arguments the callback accepts.
     * @returns {Function} Returns a callback function.
     * @example
     *
     * var characters = [
     *   { 'name': 'barney', 'age': 36 },
     *   { 'name': 'fred',   'age': 40 }
     * ];
     *
     * // wrap to create custom callback shorthands
     * _.createCallback = _.wrap(_.createCallback, function(func, callback, thisArg) {
     *   var match = /^(.+?)__([gl]t)(.+)$/.exec(callback);
     *   return !match ? func(callback, thisArg) : function(object) {
     *     return match[2] == 'gt' ? object[match[1]] > match[3] : object[match[1]] < match[3];
     *   };
     * });
     *
     * _.filter(characters, 'age__gt38');
     * // => [{ 'name': 'fred', 'age': 40 }]
     */
    function createCallback(func, thisArg, argCount) {
      var type = typeof func;
      if (func == null || type == 'function') {
        return baseCreateCallback(func, thisArg, argCount);
      }
      // handle "_.pluck" and "_.where" style callback shorthands
      return type != 'object' ? property(func) : match(func);
    }
  
    /**
     * This method returns the first argument provided to it.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {*} value Any value.
     * @returns {*} Returns `value`.
     * @example
     *
     * var object = { 'name': 'fred' };
     * _.identity(object) === object;
     * // => true
     */
    function identity(value) {
      return value;
    }
  
    /**
     * Creates a "_.where" style function, which performs a deep comparison
     * between a given object and the `props` object, returning `true` if the
     * given object has equivalent property values, else `false`.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {Object} props The object of property values to match.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var characters = [
     *   { 'name': 'fred',   'age': 40 },
     *   { 'name': 'barney', 'age': 36 }
     * ];
     *
     * var matchAge = _.match({ 'age': 36 });
     *
     * _.filter(characters, matchAge);
     * // => [{ 'name': 'barney', 'age': 36 }]
     *
     * _.find(characters, matchAge);
     * // => { 'name': 'barney', 'age': 36 }
     */
    function match(source) {
      source || (source = {});
  
      var props = keys(source);
      return function(object) {
        var length = props.length,
            result = false;
  
        while (length--) {
          var key = props[length];
          if (!(result = hasOwnProperty.call(object, key) &&
                object[key] === source[key])) {
            break;
          }
        }
        return result;
      };
    }
  
    /**
     * Adds function properties of a source object to the destination object.
     * If `object` is a function methods will be added to its prototype as well.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {Function|Object} [object=lodash] object The destination object.
     * @param {Object} source The object of functions to add.
     * @param {Object} [options] The options object.
     * @param {boolean} [options.chain=true] Specify whether the functions added are chainable.
     * @example
     *
     * function vowels(string) {
     *   return _.filter(string, function(v) {
     *     return /[aeiou]/i.test(v);
     *   });
     * }
     *
     * _.mixin({ 'vowels': vowels });
     * _.vowels('fred');
     * // => ['e']
     *
     * _('fred').vowels().value();
     * // => ['e']
     *
     * _.mixin({ 'vowels': vowels }, { 'chain': false });
     * _('fred').vowels();
     * // => ['e']
     */
    function mixin(source) {
      var index = -1,
          methodNames = functions(source),
          length = methodNames.length;
  
      while (++index < length) {
        var methodName = methodNames[index];
        lodash.prototype[methodName] = (function() {
          var func = lodash[methodName] = source[methodName];
          return function() {
            var args = [this.__wrapped__];
            push.apply(args, arguments);
  
            var result = func.apply(lodash, args);
            return this.__chain__
              ? new lodashWrapper(result, true)
              : result;
          };
        }());
      }
    }
  
    /**
     * Reverts the '_' variable to its previous value and returns a reference to
     * the `lodash` function.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @returns {Function} Returns the `lodash` function.
     * @example
     *
     * var lodash = _.noConflict();
     */
    function noConflict() {
      root._ = oldDash;
      return this;
    }
  
    /**
     * A no-operation function.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @example
     *
     * var object = { 'name': 'fred' };
     * _.noop(object) === undefined;
     * // => true
     */
    function noop() {
      // no operation performed
    }
  
    /**
     * Gets the number of milliseconds that have elapsed since the Unix epoch
     * (1 January 1970 00:00:00 UTC).
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @example
     *
     * var stamp = _.now();
     * _.defer(function() { console.log(_.now() - stamp); });
     * // => logs the number of milliseconds it took for the deferred function to be called
     */
    var now = nativeNow || function() {
      return new Date().getTime();
    };
  
    /**
     * Creates a "_.pluck" style function, which returns the `key` value of a
     * given object.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} key The name of the property to retrieve.
     * @returns {Function} Returns the new function.
     * @example
     *
     * var characters = [
     *   { 'name': 'fred',   'age': 40 },
     *   { 'name': 'barney', 'age': 36 }
     * ];
     *
     * var getName = _.property('name');
     *
     * _.map(characters, getName);
     * // => ['barney', 'fred']
     *
     * _.sortBy(characters, getName);
     * // => [{ 'name': 'barney', 'age': 36 }, { 'name': 'fred',   'age': 40 }]
     */
    function property(key) {
      return function(object) {
        return object[key];
      };
    }
  
    /**
     * Produces a random number between `min` and `max` (inclusive). If only one
     * argument is provided a number between `0` and the given number will be
     * returned. If `floating` is truey or either `min` or `max` are floats a
     * floating-point number will be returned instead of an integer.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {number} [min=0] The minimum possible value.
     * @param {number} [max=1] The maximum possible value.
     * @param {boolean} [floating=false] Specify returning a floating-point number.
     * @returns {number} Returns a random number.
     * @example
     *
     * _.random(0, 5);
     * // => an integer between 0 and 5
     *
     * _.random(5);
     * // => also an integer between 0 and 5
     *
     * _.random(5, true);
     * // => a floating-point number between 0 and 5
     *
     * _.random(1.2, 5.2);
     * // => a floating-point number between 1.2 and 5.2
     */
    function random(min, max) {
      if (min == null && max == null) {
        max = 1;
      }
      min = +min || 0;
      if (max == null) {
        max = min;
        min = 0;
      } else {
        max = +max || 0;
      }
      return min + floor(nativeRandom() * (max - min + 1));
    }
  
    /**
     * Resolves the value of property `key` on `object`. If `key` is a function
     * it will be invoked with the `this` binding of `object` and its result
     * returned, else the property value is returned. If `object` is `null` or
     * `undefined` then `undefined` is returned. If a default value is provided
     * it will be returned if the property value resolves to `undefined`.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {Object} object The object to inspect.
     * @param {string} key The name of the property to resolve.
     * @param {*} [defaultValue] The value returned if the property value
     *  resolves to `undefined`.
     * @returns {*} Returns the resolved value.
     * @example
     *
     * var object = {
     *   'name': 'fred',
     *   'age': function() {
     *     return 40;
     *   }
     * };
     *
     * _.result(object, 'name');
     * // => 'fred'
     *
     * _.result(object, 'age');
     * // => 40
     *
     * _.result(object, 'employer', 'slate');
     * // => 'slate'
     */
    function result(object, key) {
      if (object != null) {
        var value = object[key];
        return isFunction(value) ? object[key]() : value;
      }
    }
  
    /**
     * Executes the callback `n` times, returning an array of the results
     * of each callback execution. The callback is bound to `thisArg` and invoked
     * with one argument; (index).
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {number} n The number of times to execute the callback.
     * @param {Function} callback The function called per iteration.
     * @param {*} [thisArg] The `this` binding of `callback`.
     * @returns {Array} Returns an array of the results of each `callback` execution.
     * @example
     *
     * var diceRolls = _.times(3, _.partial(_.random, 1, 6));
     * // => [3, 6, 4]
     *
     * _.times(3, function(n) { mage.castSpell(n); });
     * // => calls `mage.castSpell(n)` three times, passing `n` of `0`, `1`, and `2` respectively
     *
     * _.times(3, function(n) { this.cast(n); }, mage);
     * // => also calls `mage.castSpell(n)` three times
     */
    function times(n, callback, thisArg) {
      n = (n = +n) > -1 ? n : 0;
      var index = -1,
          result = Array(n);
  
      callback = baseCreateCallback(callback, thisArg, 1);
      while (++index < n) {
        result[index] = callback(index);
      }
      return result;
    }
  
    /**
     * Generates a unique ID. If `prefix` is provided the ID will be appended to it.
     *
     * @static
     * @memberOf _
     * @category Utilities
     * @param {string} [prefix] The value to prefix the ID with.
     * @returns {string} Returns the unique ID.
     * @example
     *
     * _.uniqueId('contact_');
     * // => 'contact_104'
     *
     * _.uniqueId();
     * // => '105'
     */
    function uniqueId(prefix) {
      var id = ++idCounter + '';
      return prefix ? prefix + id : id;
    }
  
    /*--------------------------------------------------------------------------*/
  
    // add functions that return wrapped values when chaining
    lodash.after = after;
    lodash.bind = bind;
    lodash.bindAll = bindAll;
    lodash.chain = chain;
    lodash.compact = compact;
    lodash.compose = compose;
    lodash.countBy = countBy;
    lodash.debounce = debounce;
    lodash.defaults = defaults;
    lodash.defer = defer;
    lodash.delay = delay;
    lodash.difference = difference;
    lodash.filter = filter;
    lodash.flatten = flatten;
    lodash.forEach = forEach;
    lodash.functions = functions;
    lodash.groupBy = groupBy;
    lodash.indexBy = indexBy;
    lodash.initial = initial;
    lodash.intersection = intersection;
    lodash.invert = invert;
    lodash.invoke = invoke;
    lodash.keys = keys;
    lodash.map = map;
    lodash.max = max;
    lodash.memoize = memoize;
    lodash.min = min;
    lodash.omit = omit;
    lodash.once = once;
    lodash.pairs = pairs;
    lodash.partial = partial;
    lodash.pick = pick;
    lodash.pluck = pluck;
    lodash.range = range;
    lodash.reject = reject;
    lodash.rest = rest;
    lodash.shuffle = shuffle;
    lodash.sortBy = sortBy;
    lodash.tap = tap;
    lodash.throttle = throttle;
    lodash.times = times;
    lodash.toArray = toArray;
    lodash.union = union;
    lodash.uniq = uniq;
    lodash.values = values;
    lodash.where = where;
    lodash.without = without;
    lodash.wrap = wrap;
    lodash.zip = zip;
  
    // add aliases
    lodash.collect = map;
    lodash.drop = rest;
    lodash.each = forEach;
    lodash.extend = assign;
    lodash.methods = functions;
    lodash.object = zipObject;
    lodash.select = filter;
    lodash.tail = rest;
    lodash.unique = uniq;
  
    /*--------------------------------------------------------------------------*/
  
    // add functions that return unwrapped values when chaining
    lodash.clone = clone;
    lodash.contains = contains;
    lodash.escape = escape;
    lodash.every = every;
    lodash.find = find;
    lodash.has = has;
    lodash.identity = identity;
    lodash.indexOf = indexOf;
    lodash.isArguments = isArguments;
    lodash.isArray = isArray;
    lodash.isBoolean = isBoolean;
    lodash.isDate = isDate;
    lodash.isElement = isElement;
    lodash.isEmpty = isEmpty;
    lodash.isEqual = isEqual;
    lodash.isFinite = isFinite;
    lodash.isFunction = isFunction;
    lodash.isNaN = isNaN;
    lodash.isNull = isNull;
    lodash.isNumber = isNumber;
    lodash.isObject = isObject;
    lodash.isRegExp = isRegExp;
    lodash.isString = isString;
    lodash.isUndefined = isUndefined;
    lodash.lastIndexOf = lastIndexOf;
    lodash.mixin = mixin;
    lodash.noConflict = noConflict;
    lodash.random = random;
    lodash.reduce = reduce;
    lodash.reduceRight = reduceRight;
    lodash.result = result;
    lodash.size = size;
    lodash.some = some;
    lodash.sortedIndex = sortedIndex;
    lodash.template = template;
    lodash.unescape = unescape;
    lodash.uniqueId = uniqueId;
  
    // add aliases
    lodash.all = every;
    lodash.any = some;
    lodash.detect = find;
    lodash.findWhere = findWhere;
    lodash.foldl = reduce;
    lodash.foldr = reduceRight;
    lodash.include = contains;
    lodash.inject = reduce;
  
    /*--------------------------------------------------------------------------*/
  
    // add functions capable of returning wrapped and unwrapped values when chaining
    lodash.first = first;
    lodash.last = last;
    lodash.sample = sample;
  
    // add aliases
    lodash.take = first;
    lodash.head = first;
  
    /*--------------------------------------------------------------------------*/
  
    // add functions to `lodash.prototype`
    mixin(assign({}, lodash));
  
    /**
     * The semantic version number.
     *
     * @static
     * @memberOf _
     * @type string
     */
    lodash.VERSION = version;
  
    // add "Chaining" functions to the wrapper
    lodash.prototype.chain = wrapperChain;
    lodash.prototype.value = wrapperValueOf;
  
      // add `Array` mutator functions to the wrapper
      baseEach(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(methodName) {
        var func = arrayRef[methodName];
        lodash.prototype[methodName] = function() {
          var value = this.__wrapped__;
          func.apply(value, arguments);
  
          // avoid array-like object bugs with `Array#shift` and `Array#splice`
          // in Firefox < 10 and IE < 9
          if (!support.spliceObjects && value.length === 0) {
            delete value[0];
          }
          return this;
        };
      });
  
      // add `Array` accessor functions to the wrapper
      baseEach(['concat', 'join', 'slice'], function(methodName) {
        var func = arrayRef[methodName];
        lodash.prototype[methodName] = function() {
          var value = this.__wrapped__,
              result = func.apply(value, arguments);
  
          if (this.__chain__) {
            result = new lodashWrapper(result);
            result.__chain__ = true;
          }
          return result;
        };
      });
  
    /*--------------------------------------------------------------------------*/
  
    // some AMD build optimizers like r.js check for condition patterns like the following:
    if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) {
      // Expose Lo-Dash to the global object even when an AMD loader is present in
      // case Lo-Dash is loaded with a RequireJS shim config.
      // See http://requirejs.org/docs/api.html#config-shim
      root._ = lodash;
  
      // define as an anonymous module so, through path mapping, it can be
      // referenced as the "underscore" module
      define(function() {
        return lodash;
      });
    }
    // check for `exports` after `define` in case a build optimizer adds an `exports` object
    else if (freeExports && freeModule) {
      // in Node.js or RingoJS
      if (moduleExports) {
        (freeModule.exports = lodash)._ = lodash;
      }
      // in Narwhal or Rhino -require
      else {
        freeExports._ = lodash;
      }
    }
    else {
      // in a browser or Rhino
      root._ = lodash;
    }
  }.call(this));
  