Plato - node_modules/lodash/dist/lodash.underscore.js

/**
 * @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 2012-2013 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 generate unique IDs */
  var idCounter = 0;

/** Used internally to indicate various things */
  var indicatorObject = {};

/** Used to prefix keys to avoid issues with `__proto__` and properties on `Object.prototype` */
  var keyPrefix = +new Date + '';

/** Used to match "interpolate" template delimiters */
 var 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 determine if values are of the language type Object */
  var objectTypes = {
    'boolean': false,
    'function': true,
    'object': true,
    'number': false,
    'string': false,
    'undefined': false
  };

/** 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 the popular CommonJS extension `module.exports` */
  var moduleExports = freeModule && freeModule.exports === freeExports && freeExports;

/** Detect free variable `global` from Node.js or Browserified code and use it as `root` */
  var freeGlobal = objectTypes[typeof global] && global;
  if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal)) {
    root = freeGlobal;
  }

/*--------------------------------------------------------------------------*/

/**
   * The base implementation of `_.indexOf` without support for binary searches
   * or `fromIndex` constraints.
   *
   * @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 `collection` elements, stable sorting
   * 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 of `1` or `-1`.
   */
  function compareAscending(a, b) {
    var ac = a.criteria,
        bc = b.criteria,
        index = -1,
        length = ac.length;

while (++index < length) {
 var value = ac[index],
 other = bc[index];

if (value !== other) {
 if (value > other || typeof value == 'undefined') {
 return 1;
 }
 if (value < other || typeof other == 'undefined') {
 return -1;
 }
 }
 }
 // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications
 // that causes it, under certain circumstances, to return the same value for
 // `a` and `b`. See https://github.com/jashkenas/underscore/pull/1247
 //
 // This also ensures a stable sort in V8 and other engines.
 // See http://code.google.com/p/v8/issues/detail?id=90
 return a.index - b.index;
 }

/**
   * 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];
  }

/**
 * Slices the `collection` 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.
 *
 * @private
 * @param {Array|Object|string} collection The collection to slice.
 * @param {number} start The start index.
 * @param {number} end The end index.
 * @returns {Array} Returns the new array.
 */
 function slice(array, start, end) {
 start || (start = 0);
 if (typeof end == 'undefined') {
 end = array ? array.length : 0;
 }
 var index = -1,
 length = end - start || 0,
 result = Array(length < 0 ? 0 : length);

while (++index < length) {
 result[index] = array[start + index];
 }
 return result;
 }

/*--------------------------------------------------------------------------*/

/**
   * Used for `Array` method references.
   *
   * Normally `Array.prototype` would suffice, however, using an array literal
   * avoids issues in Narwhal.
   */
  var arrayRef = [];

/** Used for native method references */
  var 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| for [^\]]+/g, '.*?') + '$'
  );

/** Native method shortcuts */
  var ceil = Math.ceil,
      floor = Math.floor,
      hasOwnProperty = objectProto.hasOwnProperty,
      push = arrayRef.push,
      propertyIsEnumerable = objectProto.propertyIsEnumerable;

/* 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,
      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`, `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`, `max`, `memoize`, `merge`, `min`, `object`, `omit`,
   * `once`, `pairs`, `partial`, `partialRight`, `pick`, `pluck`, `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`,
   * and `zip`
   *
   * The non-chainable wrapper functions are:
   * `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`, `parseInt`, `pop`, `random`, `reduce`,
   * `reduceRight`, `result`, `shift`, `size`, `some`, `sortedIndex`, `runInContext`,
   * `template`, `unescape`, `uniqueId`, and `value`
   *
   * The wrapper functions `first` and `last` 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 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 = (arrayRef.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': /<%-([\s\S]+?)%>/g,

/**
 * Used to detect code to be evaluated.
 *
 * @memberOf _.templateSettings
 * @type RegExp
 */
 'evaluate': /<%([\s\S]+?)%>/g,

/**
     * 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} bindData The bind data array.
   * @returns {Function} Returns the new bound function.
   */
  function baseBind(bindData) {
    var func = bindData[0],
        partialArgs = bindData[2],
        thisArg = bindData[4];

/**
   * 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, properties) {
    return isObject(prototype) ? nativeCreate(prototype) : {};
  }
  // fallback for browsers 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} bindData The bind data array.
   * @returns {Function} Returns the new function.
   */
  function baseCreateWrapper(bindData) {
    var func = bindData[0],
        bitmask = bindData[1],
        partialArgs = bindData[2],
        partialRightArgs = bindData[3],
        thisArg = bindData[4],
        arity = bindData[5];

var isBind = bitmask & 1,
        isBindKey = bitmask & 2,
        isCurry = bitmask & 4,
        isCurryBound = bitmask & 8,
        key = func;

/**
   * 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 `_.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 `_.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 && objectTypes[type]) &&
        !(b && objectTypes[otherType])) {
      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 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 {
      forIn(b, function(value, key, b) {
        if (hasOwnProperty.call(b, key)) {
          size++;
          return !(result = hasOwnProperty.call(a, key) && baseIsEqual(a[key], value, stackA, stackB)) && indicatorObject;
        }
      });

if (result) {
        forIn(a, function(value, key, a) {
          if (hasOwnProperty.call(a, key)) {
            return !(result = --size > -1) && indicatorObject;
          }
        });
      }
    }
    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 {
 forOwn(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 method 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 {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.
   * @param {*} [thisArg] The `this` binding of `func`.
   * @param {number} [arity] The arity of `func`.
   * @returns {Function} Returns the new function.
   */
  function createWrapper(func, bitmask, partialArgs, partialRightArgs, thisArg, arity) {
    var isBind = bitmask & 1,
        isBindKey = bitmask & 2,
        isCurry = bitmask & 4,
        isCurryBound = bitmask & 8,
        isPartial = bitmask & 16,
        isPartialRight = bitmask & 32;

if (!isBindKey && !isFunction(func)) {
      throw new TypeError;
    }
    if (isPartial && !partialArgs.length) {
      bitmask &= ~16;
      isPartial = partialArgs = false;
    }
    if (isPartialRight && !partialRightArgs.length) {
      bitmask &= ~32;
      isPartialRight = partialRightArgs = false;
    }
    // fast path for `_.bind`
    var creater = (bitmask == 1 || bitmask === 17) ? baseBind : baseCreateWrapper;
    return creater([func, bitmask, partialArgs, partialRightArgs, thisArg, arity]);
  }

/**
   * 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];
  }

/**
   * 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(value);
  }

/**
   * 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];
  }

/*--------------------------------------------------------------------------*/

/**
   * 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 browsers 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;
    };
  }

/**
   * 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;
  };

/**
   * 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 index, iterable = object, result = [];
    if (!iterable) return result;
    if (!(objectTypes[typeof object])) return result;
      for (index in iterable) {
        if (hasOwnProperty.call(iterable, index)) {
          result.push(index);
        }
      }
    return result
  };

/**
   * 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);
  };

/**
 * Used to convert characters to HTML entities:
 *
 * 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 an unquoted attribute value.
 * http://mathiasbynens.be/notes/ambiguous-ampersands (under "semi-related fun fact")
 */
 var htmlEscapes = {
 '&': '&amp;',
 '<': '&lt;',
 '>': '&gt;',
 '"': '&quot;',
 "'": '&#x27;'
 };

/** Used to convert HTML entities to characters */
  var htmlUnescapes = invert(htmlEscapes);

/** Used to match HTML entities and HTML characters */
  var reEscapedHtml = RegExp('(' + keys(htmlUnescapes).join('|') + ')', 'g'),
      reUnescapedHtml = RegExp('[' + keys(htmlEscapes).join('') + ']', 'g');

/*--------------------------------------------------------------------------*/

/**
 * 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 _
 * @type Function
 * @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;
 * });
 *
 * var object = { 'name': 'barney' };
 * defaults(object, { 'name': 'fred', 'employer': 'slate' });
 * // => { 'name': 'barney', 'employer': 'slate' }
 */
 function assign(object) {
 if (!object) {
 return object;
 }
 for (var argsIndex = 1, argsLength = arguments.length; argsIndex < argsLength; argsIndex++) {
 var iterable = arguments[argsIndex];
 if (iterable) {
 for (var key in iterable) {
 object[key] = iterable[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).
   *
   * @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 _
 * @type Function
 * @category Objects
 * @param {Object} object The destination object.
 * @param {...Object} [source] The source objects.
 * @param- {Object} [guard] Allows working with `_.reduce` without using its
 * `key` and `object` arguments as sources.
 * @returns {Object} Returns the destination object.
 * @example
 *
 * var object = { 'name': 'barney' };
 * _.defaults(object, { 'name': 'fred', 'employer': 'slate' });
 * // => { 'name': 'barney', 'employer': 'slate' }
 */
 function defaults(object) {
 if (!object) {
 return object;
 }
 for (var argsIndex = 1, argsLength = arguments.length; argsIndex < argsLength; argsIndex++) {
 var iterable = arguments[argsIndex];
 if (iterable) {
 for (var key in iterable) {
 if (typeof object[key] == 'undefined') {
 object[key] = iterable[key];
 }
 }
 }
 }
 return object;
 }

/**
   * Iterates over own and inherited enumerable properties of an object,
   * executing the callback for each property. The callback is bound to `thisArg`
   * and invoked with three arguments; (value, key, object). Callbacks may exit
   * iteration early by explicitly returning `false`.
   *
   * @static
   * @memberOf _
   * @type Function
   * @category Objects
   * @param {Object} object The object to iterate over.
   * @param {Function} [callback=identity] The function called per iteration.
   * @param {*} [thisArg] The `this` binding of `callback`.
   * @returns {Object} Returns `object`.
   * @example
   *
   * function Shape() {
   *   this.x = 0;
   *   this.y = 0;
   * }
   *
   * Shape.prototype.move = function(x, y) {
   *   this.x += x;
   *   this.y += y;
   * };
   *
   * _.forIn(new Shape, function(value, key) {
   *   console.log(key);
   * });
   * // => logs 'x', 'y', and 'move' (property order is not guaranteed across environments)
   */
  var forIn = function(collection, callback) {
    var index, iterable = collection, result = iterable;
    if (!iterable) return result;
    if (!objectTypes[typeof iterable]) return result;
      for (index in iterable) {
        if (callback(iterable[index], index, collection) === indicatorObject) return result;
      }
    return result
  };

/**
   * Iterates over own enumerable properties of an object, executing the callback
   * for each property. The callback is bound to `thisArg` and invoked with three
   * arguments; (value, key, object). Callbacks may exit iteration early by
   * explicitly returning `false`.
   *
   * @static
   * @memberOf _
   * @type Function
   * @category Objects
   * @param {Object} object The object to iterate over.
   * @param {Function} [callback=identity] The function called per iteration.
   * @param {*} [thisArg] The `this` binding of `callback`.
   * @returns {Object} Returns `object`.
   * @example
   *
   * _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(num, key) {
   *   console.log(key);
   * });
   * // => logs '0', '1', and 'length' (property order is not guaranteed across environments)
   */
  var forOwn = function(collection, callback) {
    var index, iterable = collection, result = iterable;
    if (!iterable) return result;
    if (!objectTypes[typeof iterable]) return result;
      for (index in iterable) {
        if (hasOwnProperty.call(iterable, index)) {
          if (callback(iterable[index], index, collection) === indicatorObject) return result;
        }
      }
    return result
  };

/**
   * 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 = [];
    forIn(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.
   *
   * @static
   * @memberOf _
   * @category Objects
   * @param {Object} object The object to invert.
   * @returns {Object} Returns the created inverted object.
   * @example
   *
   * _.invert({ 'first': 'fred', 'second': 'barney' });
   * // => { 'fred': 'first', '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 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 is not the same as native `isFinite` which will return true for
   * booleans and empty strings. See http://es5.github.io/#x15.1.2.5.
   *
   * @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
    return !!(value && objectTypes[typeof value]);
  }

/**
   * Checks if `value` is `NaN`.
   *
   * Note: This is not the same as native `isNaN` which will return `true` for
   * `undefined` and other non-numeric values. See http://es5.github.io/#x15.1.2.4.
   *
   * @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 http://es5.github.io/#x8.5.
   *
   * @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) {
    return typeof value == 'number' ||
      value && typeof value == '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) {
    return value && objectTypes[typeof value] && 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 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 properties to omit or the
   *  function called per iteration.
   * @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) {
    var props = [];
    forIn(object, function(value, key) {
      props.push(key);
    });
    props = baseDifference(props, baseFlatten(arguments, true, false, 1));

var index = -1,
        length = props.length,
        result = {};

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) {
    var index = -1,
        props = baseFlatten(arguments, 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;
 }

/*--------------------------------------------------------------------------*/

/**
   * 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 {
      forOwn(collection, function(value) {
        return (result = value === target) && indicatorObject;
      });
    }
    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 given 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 {
 forOwn(collection, function(value, index, collection) {
 return !(result = !!callback(value, index, collection)) && indicatorObject;
 });
 }
 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 {
 forOwn(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;
 forOwn(collection, function(value, index, collection) {
 if (callback(value, index, collection)) {
 result = value;
 return indicatorObject;
 }
 });
 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) === indicatorObject) {
 break;
 }
 }
 } else {
 forOwn(collection, callback);
 }
 }

/**
   * This method is like `_.forEach` except that it iterates over elements
   * of a `collection` from right to left.
   *
   * @static
   * @memberOf _
   * @alias eachRight
   * @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]).forEachRight(function(num) { console.log(num); }).join(',');
   * // => logs each number from right to left and returns '3,2,1'
   */
  function forEachRight(collection, callback) {
    var length = collection ? collection.length : 0;
    if (typeof length == 'number') {
      while (length--) {
        if (callback(collection[length], length, collection) === false) {
          break;
        }
      }
    } else {
      var props = keys(collection);
      length = props.length;
      forOwn(collection, function(value, key, collection) {
        key = props ? props[--length] : --length;
        return callback(collection[key], key, collection) === false && indicatorObject;
      });
    }
  }

/**
   * 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) {
    (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(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 {...*} [arg] 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 args = slice(arguments, 2),
        index = -1,
        isFunc = typeof methodName == 'function',
        length = collection ? collection.length : 0,
        result = Array(typeof length == 'number' ? length : 0);

forEach(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 = [];
 forOwn(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;

// allows working with functions like `_.map` without using
    // their `index` argument as a callback
    if (typeof callback != 'function' && 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);

forEach(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;

if (callback == null && typeof length == 'number') {
 while (++index < length) {
 var value = collection[index];
 if (value < result) {
 result = value;
 }
 }
 } else {
 callback = createCallback(callback, thisArg, 3);

forEach(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} property 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) {
 if (!collection) return accumulator;
 var noaccum = arguments.length < 3;
 callback = createCallback(callback, thisArg, 4);

var index = -1,
        length = collection.length;

if (typeof length == 'number') {
 if (noaccum) {
 accumulator = collection[++index];
 }
 while (++index < length) {
 accumulator = callback(accumulator, collection[index], index, collection);
 }
 } else {
 forOwn(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);
 forEachRight(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] Allows working with functions like `_.map`
   *  without using their `index` arguments as `n`.
   * @returns {Array} 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 http://en.wikipedia.org/wiki/Fisher-Yates_shuffle.
   *
   * @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);

forEach(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 {
 forOwn(collection, function(value, index, collection) {
 return (result = callback(value, index, collection)) && indicatorObject;
 });
 }
 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);
    forEach(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 of each element in a `collection` to the given
   * `properties` 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 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,
        result = [];

while (++index < length) {
 var value = array[index];
 if (value) {
 result.push(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
 *
 * _.first([1, 2, 3], 2);
 * // => [1, 2]
 *
 * _.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, nativeMin(nativeMax(0, n), length));
 }

/**
   * 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];
   *
   * _.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) {
    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
 *
 * _.indexOf([1, 2, 3, 1, 2, 3], 2, 3);
 * // => 4
 *
 * _.indexOf([1, 1, 2, 2, 3, 3], 2, true);
 * // => 2
 */
 function indexOf(array, value, fromIndex) {
 if (typeof fromIndex == 'number') {
 var length = array ? array.length : 0;
 fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex || 0);
 } else if (fromIndex) {
 var index = sortedIndex(array, value);
 return 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]
   *
   * _.initial([1, 2, 3], 2);
   * // => [1]
   *
   * _.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;
    }
    return slice(array, 0, nativeMin(nativeMax(0, length - n), length));
  }

/**
   * 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
   *
   * _.last([1, 2, 3], 2);
   * // => [2, 3]
   *
   * _.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;
      }
    }
    return slice(array, nativeMax(0, length - n));
  }

/**
 * 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
 *
 * _.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]
 *
 * _.rest([1, 2, 3], 2);
 * // => [3]
 *
 * _.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 {
 n = (callback == null || thisArg) ? 1 : nativeMax(0, callback);
 }
 return slice(array, n);
 }

/**
   * 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
   *
   * // using "_.pluck" callback shorthand
   * _.sortedIndex([{ 'x': 20 }, { 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
   * // => 2
   *
   * var dict = {
   *   'wordToNumber': { 'twenty': 20, 'thirty': 30, 'fourty': 40, 'fifty': 50 }
   * };
   *
   * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
   *   return dict.wordToNumber[word];
   * });
   * // => 2
   *
   * _.sortedIndex(['twenty', 'thirty', 'fifty'], 'fourty', function(word) {
   *   return this.wordToNumber[word];
   * }, dict);
   * // => 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]
   *
   * _.uniq([1, 1, 2, 2, 3], true);
   * // => [1, 2, 3]
   *
   * _.uniq(['A', 'b', 'C', 'a', 'B', 'c'], function(letter) { return letter.toLowerCase(); });
   * // => ['A', 'b', 'C']
   *
   * _.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) {
    // juggle arguments
    if (typeof isSorted != 'boolean' && isSorted != null) {
      thisArg = callback;
      callback = (typeof isSorted != 'function' && thisArg && thisArg[isSorted] === array) ? null : isSorted;
      isSorted = false;
    }
    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.
 *
 * @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]]
 */
 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 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.
   *
   * @static
   * @memberOf _
   * @category Functions
   * @param {Function} func The function to bind.
   * @param {*} [thisArg] The `this` binding of `func`.
   * @param {...*} [arg] 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) {
    return arguments.length > 2
      ? createWrapper(func, 17, slice(arguments, 2), null, thisArg)
      : createWrapper(func, 1, null, null, thisArg);
  }

/**
   * 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.
   *
   * @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], 1, null, 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,
        length = funcs.length;

while (length--) {
      if (!isFunction(funcs[length])) {
        throw new TypeError;
      }
    }
    return function() {
      var args = arguments,
          length = funcs.length;

while (length--) {
        args = [funcs[length].apply(this, args)];
      }
      return args[0];
    };
  }

/**
   * 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);
 }
 };

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 {...*} [arg] 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 {...*} [arg] 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) : keyPrefix + 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.
   *
   * @static
   * @memberOf _
   * @category Functions
   * @param {Function} func The function to partially apply arguments to.
   * @param {...*} [arg] 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) {
    return createWrapper(func, 16, slice(arguments, 1));
  }

/**
   * 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 '' + func(text) + '';
 * });
 *
 * p('Fred, Wilma, & Pebbles');
 * // => 'Fred, Wilma, &amp; Pebbles'
 */
 function wrap(value, wrapper) {
 return createWrapper(wrapper, 16, [value]);
 }

/*--------------------------------------------------------------------------*/

/**
 * 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 _
 * @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" style callback shorthands
 if (type != 'object') {
 return property(func);
 }
 var props = keys(func);
 return function(object) {
 var length = props.length,
 result = false;

while (length--) {
        if (!(result = object[props[length]] === func[props[length]])) {
          break;
        }
      }
      return result;
    };
  }

/**
 * Converts the characters `&`, `<`, `>`, `"`, and `'` in `string` to their
 * corresponding HTML entities.
 *
 * @static
 * @memberOf _
 * @category Utilities
 * @param {string} string The string to escape.
 * @returns {string} Returns the escaped string.
 * @example
 *
 * _.escape('Fred, Wilma, & Pebbles');
 * // => 'Fred, Wilma, &amp; Pebbles'
 */
 function escape(string) {
 return string == null ? '' : String(string).replace(reUnescapedHtml, escapeHtmlChar);
 }

/**
   * 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;
  }

/**
   * 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 capitalize(string) {
   *   return string.charAt(0).toUpperCase() + string.slice(1).toLowerCase();
   * }
   *
   * _.mixin({ 'capitalize': capitalize });
   * _.capitalize('fred');
   * // => 'Fred'
   *
   * _('fred').capitalize().value();
   * // => 'Fred'
   *
   * _.mixin({ 'capitalize': capitalize }, { 'chain': false });
   * _('fred').capitalize();
   * // => 'Fred'
   */
  function mixin(object) {
    forEach(functions(object), function(methodName) {
      var func = lodash[methodName] = object[methodName];

lodash.prototype[methodName] = 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 = isNative(now = Date.now) && now || 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 falsey then `undefined`
   * is returned.
   *
   * @static
   * @memberOf _
   * @category Utilities
   * @param {Object} object The object to inspect.
   * @param {string} key The name of the property to resolve.
   * @returns {*} Returns the resolved value.
   * @example
   *
   * var object = {
   *   'cheese': 'crumpets',
   *   'stuff': function() {
   *     return 'nonsense';
   *   }
   * };
   *
   * _.result(object, 'cheese');
   * // => 'crumpets'
   *
   * _.result(object, 'stuff');
   * // => 'nonsense'
   */
  function result(object, key) {
    if (object) {
      var value = object[key];
      return isFunction(value) ? object[key]() : value;
    }
  }

/**
 * 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 http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl
 *
 * For more information on precompiling templates see:
 * http://lodash.com/custom-builds
 *
 * For more information on Chrome extension sandboxes see:
 * http://developer.chrome.com/stable/extensions/sandboxingEval.html
 *
 * @static
 * @memberOf _
 * @category Utilities
 * @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} [sourceURL] The sourceURL of the template's compiled source.
 * @param {string} [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('<%- value %>', { 'value': '<script>' });
 * // => '&lt;script&gt;'
 *
 * // 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;
  }

/**
   * 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;
 }

/**
   * The inverse of `_.escape` this method converts the HTML entities
   * `&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to their
   * corresponding characters.
   *
   * @static
   * @memberOf _
   * @category Utilities
   * @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) {
    return string == null ? '' : String(string).replace(reEscapedHtml, unescapeHtmlChar);
  }

/**
   * 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;
  }

/*--------------------------------------------------------------------------*/

/**
   * Creates a `lodash` object that wraps the given 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;
  }

/**
   * Invokes `interceptor` with the `value` as the first argument and then
   * returns `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.
   * @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__;
  }

/*--------------------------------------------------------------------------*/

// 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(lodash);

/**
   * The semantic version number.
   *
   * @static
   * @memberOf _
   * @type string
   */
  lodash.VERSION = '2.4.1';

// add "Chaining" functions to the wrapper
  lodash.prototype.chain = wrapperChain;
  lodash.prototype.value = wrapperValueOf;

// add `Array` mutator functions to the wrapper
    forEach(['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
    forEach(['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));

node_modules/lodash/dist/lodash.underscore.js

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