/**
* @license
* Lo-Dash 3.0.0-pre (Custom Build)
* Build: `lodash underscore -o ./dist/lodash.underscore.js`
* Copyright 2012-2014 The Dojo Foundation
* Based on Underscore.js 1.7.0
* Copyright 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license
*/
;(function() {
/** Used as a safe reference for `undefined` in pre ES5 environments */
var undefined;
/** Used as the semantic version number */
var VERSION = '3.0.0-pre';
/** Used by methods to exit iteration */
var BREAK_INDICATOR = '__lodash_breaker__';
/** Used to compose bitmasks for wrapper metadata */
var BIND_FLAG = 1,
BIND_KEY_FLAG = 2,
CURRY_FLAG = 4,
CURRY_RIGHT_FLAG = 8,
CURRY_BOUND_FLAG = 16,
PARTIAL_FLAG = 32;
/** Used as the TypeError message for "Functions" methods */
var FUNC_ERROR_TEXT = 'Expected a function';
/** Used as references for the max length and index of an array */
var MAX_ARRAY_LENGTH = Math.pow(2, 32) - 1,
MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1;
/**
* Used as the maximum length of an array-like value.
* See the [ES6 spec](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength)
* for more details.
*/
var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
/** Used as the internal argument placeholder */
var PLACEHOLDER = '__lodash_placeholder__';
/** Used to generate unique IDs */
var idCounter = 0;
/** Used to match HTML entities and HTML characters */
var reEscapedHtml = /&(?:amp|lt|gt|quot|#x27|#96);/g,
reUnescapedHtml = /[&<>"'`]/g;
/** Used to match template delimiters */
var reEscape = /<%-([\s\S]+?)%>/g,
reEvaluate = /<%([\s\S]+?)%>/g,
reInterpolate = /<%=([\s\S]+?)%>/g;
/** Used to detect host constructors (Safari > 5) */
var reHostCtor = /^\[object .+?Constructor\]$/;
/** Used to ensure capturing order of template delimiters */
var reNoMatch = /($^)/;
/**
* Used to match `RegExp` special characters.
* See this [article on `RegExp` characters](http://www.regular-expressions.info/characters.html#special)
* for more details.
*/
var reRegExpChars = /[.*+?^${}()|[\]\/\\]/g;
/** Used to match unescaped characters in compiled string literals */
var reUnescapedString = /['\n\r\u2028\u2029\\]/g;
/** `Object#toString` result references */
var argsClass = '[object Arguments]',
arrayClass = '[object Array]',
boolClass = '[object Boolean]',
dateClass = '[object Date]',
errorClass = '[object Error]',
funcClass = '[object Function]',
mapClass = '[object Map]',
numberClass = '[object Number]',
objectClass = '[object Object]',
regexpClass = '[object RegExp]',
setClass = '[object Set]',
stringClass = '[object String]',
weakMapClass = '[object WeakMap]';
var arrayBufferClass = '[object ArrayBuffer]',
float32Class = '[object Float32Array]',
float64Class = '[object Float64Array]',
int8Class = '[object Int8Array]',
int16Class = '[object Int16Array]',
int32Class = '[object Int32Array]',
uint8Class = '[object Uint8Array]',
uint8ClampedClass = '[object Uint8ClampedArray]',
uint16Class = '[object Uint16Array]',
uint32Class = '[object Uint32Array]';
/** Used to identify object classifications that are treated like arrays */
var arrayLikeClasses = {};
arrayLikeClasses[argsClass] =
arrayLikeClasses[arrayClass] = arrayLikeClasses[float32Class] =
arrayLikeClasses[float64Class] = arrayLikeClasses[int8Class] =
arrayLikeClasses[int16Class] = arrayLikeClasses[int32Class] =
arrayLikeClasses[uint8Class] = arrayLikeClasses[uint8ClampedClass] =
arrayLikeClasses[uint16Class] = arrayLikeClasses[uint32Class] = true;
arrayLikeClasses[arrayBufferClass] = arrayLikeClasses[boolClass] =
arrayLikeClasses[dateClass] = arrayLikeClasses[errorClass] =
arrayLikeClasses[funcClass] = arrayLikeClasses[mapClass] =
arrayLikeClasses[numberClass] = arrayLikeClasses[objectClass] =
arrayLikeClasses[regexpClass] = arrayLikeClasses[setClass] =
arrayLikeClasses[stringClass] = arrayLikeClasses[weakMapClass] = false;
/**
* Used to map characters to HTML entities.
*
* **Note:** Though the ">" character is escaped for symmetry, characters like
* ">" and "/" don't require escaping in HTML and have no special meaning
* unless they're part of a tag or unquoted attribute value.
* See [Mathias Bynens's article](http://mathiasbynens.be/notes/ambiguous-ampersands)
* (under "semi-related fun fact") for more details.
*
* Backticks are escaped because in Internet Explorer < 9, they can break out
* of attribute values or HTML comments. See [#102](http://html5sec.org/#102),
* [#108](http://html5sec.org/#108), and [#133](http://html5sec.org/#133) of
* the [HTML5 Security Cheatsheet](http://html5sec.org/) for more details.
*/
var htmlEscapes = {
'&': '&',
'<': '<',
'>': '>',
'"': '"',
"'": ''',
'`': '`'
};
/** Used to map HTML entities to characters */
var htmlUnescapes = {
'&': '&',
'<': '<',
'>': '>',
'"': '"',
''': "'",
'`': '`'
};
/** Used to determine if values are of the language type `Object` */
var objectTypes = {
'function': true,
'object': true
};
/** Used to escape characters for inclusion in compiled string literals */
var stringEscapes = {
'\\': '\\',
"'": "'",
'\n': 'n',
'\r': 'r',
'\u2028': 'u2028',
'\u2029': 'u2029'
};
/** Used as a reference to the global object */
var root = (objectTypes[typeof window] && window) || this;
/** Detect free variable `exports` */
var freeExports = objectTypes[typeof exports] && exports && !exports.nodeType && exports;
/** Detect free variable `module` */
var freeModule = objectTypes[typeof module] && module && !module.nodeType && module;
/** Detect free variable `global` from Node.js or Browserified code and use it as `root` */
var freeGlobal = freeExports && freeModule && typeof global == 'object' && global;
if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal || freeGlobal.self === freeGlobal)) {
root = freeGlobal;
}
/** Detect the popular CommonJS extension `module.exports` */
var moduleExports = freeModule && freeModule.exports === freeExports && freeExports;
/*--------------------------------------------------------------------------*/
/**
* A specialized version of `_.forEach` for arrays without support for
* callback shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns `array`.
*/
function arrayEach(array, iteratee) {
var index = -1,
length = array.length;
while (++index < length) {
if (iteratee(array[index], index, array) === BREAK_INDICATOR) {
break;
}
}
return array;
}
/**
* A specialized version of `_.every` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns `true` if all elements pass the predicate check,
* else `false`
*/
function arrayEvery(array, predicate) {
var index = -1,
length = array.length;
while (++index < length) {
if (!predicate(array[index], index, array)) {
return false;
}
}
return true;
}
/**
* A specialized version of `_.map` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns the new mapped array.
*/
function arrayMap(array, iteratee) {
var index = -1,
length = array.length,
result = Array(length);
while (++index < length) {
result[index] = iteratee(array[index], index, array);
}
return result;
}
/**
* A specialized version of `_.filter` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns the new filtered array.
*/
function arrayFilter(array, predicate) {
var index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index];
if (predicate(value, index, array)) {
result[++resIndex] = value;
}
}
return result;
}
/**
* A specialized version of `_.reduce` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {boolean} [initFromArray=false] Specify using the first element of
* `array` as the initial value.
* @returns {*} Returns the accumulated value.
*/
function arrayReduce(array, iteratee, accumulator, initFromArray) {
var index = -1,
length = array.length;
if (initFromArray && length) {
accumulator = array[++index];
}
while (++index < length) {
accumulator = iteratee(accumulator, array[index], index, array);
}
return accumulator;
}
/**
* A specialized version of `_.reduceRight` for arrays without support for
* callback shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {boolean} [initFromArray=false] Specify using the last element of
* `array` as the initial value.
* @returns {*} Returns the accumulated value.
*/
function arrayReduceRight(array, iteratee, accumulator, initFromArray) {
var length = array.length;
if (initFromArray && length) {
accumulator = array[--length];
}
while (length--) {
accumulator = iteratee(accumulator, array[length], length, array);
}
return accumulator;
}
/**
* A specialized version of `_.some` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
*/
function arraySome(array, predicate) {
var index = -1,
length = array.length;
while (++index < length) {
if (predicate(array[index], index, array)) {
return true;
}
}
return false;
}
/**
* The base implementation of `compareAscending` which compares values and
* sorts them in ascending order without guaranteeing a stable sort.
*
* @private
* @param {*} value The value to compare to `other`.
* @param {*} other The value to compare to `value`.
* @returns {number} Returns the sort order indicator for `value`.
*/
function baseCompareAscending(value, other) {
if (value !== other) {
var valIsReflexive = value === value,
othIsReflexive = other === other;
if (value > other || !valIsReflexive || (typeof value == 'undefined' && othIsReflexive)) {
return 1;
}
if (value < other || !othIsReflexive || (typeof other == 'undefined' && valIsReflexive)) {
return -1;
}
}
return 0;
}
/**
* The base implementation of `_.indexOf` without support for `fromIndex`
* bounds checks and binary searches.
*
* @private
* @param {Array} array The array to search.
* @param {*} value The value to search for.
* @param {number} [fromIndex=0] The index to search from.
* @returns {number} Returns the index of the matched value, else `-1`.
*/
function baseIndexOf(array, value, fromIndex) {
if (value !== value) {
return indexOfNaN(array, fromIndex);
}
var index = (fromIndex || 0) - 1,
length = array.length;
while (++index < length) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* The base implementation of `_.slice` without support for `start` and `end`
* arguments.
*
* @private
* @param {Array} array The array to slice.
* @returns {Array} Returns the slice of `array`.
*/
function baseSlice(array) {
var index = -1,
length = array ? array.length : 0,
result = Array(length);
while (++index < length) {
result[index] = array[index];
}
return result;
}
/**
* Used by `_.sortBy` to compare transformed elements of `collection` and stable
* sort them in ascending order.
*
* @private
* @param {Object} object The object to compare to `other`.
* @param {Object} other The object to compare to `object`.
* @returns {number} Returns the sort order indicator for `object`.
*/
function compareAscending(object, other) {
return baseCompareAscending(object.criteria, other.criteria) || (object.index - other.index);
}
/**
* Used by `_.escape` to convert characters to HTML entities.
*
* @private
* @param {string} chr The matched character to escape.
* @returns {string} Returns the escaped character.
*/
function escapeHtmlChar(chr) {
return htmlEscapes[chr];
}
/**
* Used by `_.template` to escape characters for inclusion in compiled
* string literals.
*
* @private
* @param {string} chr The matched character to escape.
* @returns {string} Returns the escaped character.
*/
function escapeStringChar(chr) {
return '\\' + stringEscapes[chr];
}
/**
* Gets the index at which the first occurrence of `NaN` is found in `array`.
* If `fromRight` is provided elements of `array` are iterated from right to left.
*
* @private
* @param {Array} array The array to search.
* @param {number} [fromIndex] The index to search from.
* @param {boolean} [fromRight=false] Specify iterating from right to left.
* @returns {number} Returns the index of the matched `NaN`, else `-1`.
*/
function indexOfNaN(array, fromIndex, fromRight) {
var length = array.length,
index = fromRight ? (fromIndex || length) : ((fromIndex || 0) - 1);
while ((fromRight ? index-- : ++index < length)) {
var other = array[index];
if (other !== other) {
return index;
}
}
return -1;
}
/**
* Checks if the provided arguments are from an iteratee call.
*
* @private
* @param {*} value The potential iteratee value argument.
* @param {*} index The potential iteratee index or key argument.
* @param {*} object The potential iteratee object argument.
* @returns {boolean} Returns `true` if the arguments are from an iteratee call, else `false`.
*/
function isIterateeCall(value, index, object) {
var indexType = typeof index,
objectType = typeof object;
return (object && (indexType == 'number' || indexType == 'string') &&
(objectType == 'function' || objectType == 'object') && object[index] === value) || false;
}
/**
* Replaces all `placeholder` elements in `array` with an internal placeholder
* and returns an array of their indexes.
*
* @private
* @param {Array} array The array to modify.
* @param {*} placeholder The placeholder to replace.
* @returns {Array} Returns the new array of placeholder indexes.
*/
function replaceHolders(array, placeholder) {
var index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
if (array[index] === placeholder) {
array[index] = PLACEHOLDER;
result[++resIndex] = index;
}
}
return result;
}
/**
* An implementation of `_.uniq` optimized for sorted arrays without support
* for callback shorthands and `this` binding.
*
* @private
* @param {Array} array The array to inspect.
* @param {Function} [iteratee] The function invoked per iteration.
* @returns {Array} Returns the new duplicate-value-free array.
*/
function sortedUniq(array, iteratee) {
var seen,
index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index],
computed = iteratee ? iteratee(value, index, array) : value;
if (!index || seen !== computed) {
seen = computed;
result[++resIndex] = value;
}
}
return result;
}
/**
* Used by `_.unescape` to convert HTML entities to characters.
*
* @private
* @param {string} chr The matched character to unescape.
* @returns {string} Returns the unescaped character.
*/
function unescapeHtmlChar(chr) {
return htmlUnescapes[chr];
}
/*--------------------------------------------------------------------------*/
/** Used for native method references */
var arrayProto = Array.prototype,
objectProto = Object.prototype;
/** Used to resolve the decompiled source of functions */
var fnToString = Function.prototype.toString;
/** Used to check objects for own properties */
var hasOwnProperty = objectProto.hasOwnProperty;
/** 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('^' +
escapeRegExp(toString)
.replace(/toString|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
);
/** Native method references */
var ceil = Math.ceil,
floor = Math.floor,
push = arrayProto.push,
propertyIsEnumerable = objectProto.propertyIsEnumerable,
splice = arrayProto.splice;
/* Native method references for those with the same name as other `lodash` methods */
var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate,
nativeIsArray = isNative(nativeIsArray = Array.isArray) && nativeIsArray,
nativeIsFinite = root.isFinite,
nativeKeys = isNative(nativeKeys = Object.keys) && nativeKeys,
nativeMax = Math.max,
nativeMin = Math.min,
nativeNow = isNative(nativeNow = Date.now) && nativeNow,
nativeRandom = Math.random;
/*------------------------------------------------------------------------*/
/**
* Creates a `lodash` object which wraps the given value to enable intuitive
* method chaining.
*
* In addition to Lo-Dash methods, wrappers also have the following `Array` methods:
* `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`,
* and `unshift`
*
* Chaining is supported in custom builds as long as the `value` method is
* implicitly or explicitly included in the build.
*
* The chainable wrapper functions are:
* `after`, `assign`, `at`, `before`, `bind`, `bindAll`, `bindKey`, `callback`,
* `chain`, `chunk`, `compact`, `concat`, `constant`, `countBy`, `create`,
* `curry`, `debounce`, `defaults`, `defer`, `delay`, `difference`, `drop`,
* `dropRight`, `dropRightWhile`, `dropWhile`, `filter`, `flatten`, `flattenDeep`,
* `flow`, `flowRight`, `forEach`, `forEachRight`, `forIn`, `forInRight`,
* `forOwn`, `forOwnRight`, `functions`, `groupBy`, `indexBy`, `initial`,
* `intersection`, `invert`, `invoke`, `keys`, `keysIn`, `map`, `mapValues`,
* `matches`, `memoize`, `merge`, `mixin`, `negate`, `noop`, `omit`, `once`,
* `pairs`, `partial`, `partialRight`, `partition`, `pick`, `pluck`, `property`,
* `pull`, `pullAt`, `push`, `range`, `reject`, `remove`, `rest`, `reverse`,
* `shuffle`, `slice`, `sort`, `sortBy`, `splice`, `take`, `takeRight`,
* `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `times`,
* `toArray`, `transform`, `union`, `uniq`, `unshift`, `unzip`, `values`,
* `valuesIn`, `where`, `without`, `wrap`, `xor`, `zip`, and `zipObject`
*
* The non-chainable wrapper functions are:
* `attempt`, `camelCase`, `capitalize`, `clone`, `cloneDeep`, `contains`,
* `deburr`, endsWith`, `escape`, `escapeRegExp`, `every`, `find`, `findIndex`,
* `findKey`, `findLast`, `findLastIndex`, `findLastKey`, `findWhere`, `first`,
* `has`, `identity`, `indexOf`, `isArguments`, `isArray`, `isBoolean`, isDate`,
* `isElement`, `isEmpty`, `isEqual`, `isError`, `isFinite`, `isFunction`,
* `isNative`, `isNaN`, `isNull`, `isNumber`, `isObject`, `isPlainObject`,
* `isRegExp`, `isString`, `isUndefined`, `join`, `kebabCase`, `last`,
* `lastIndexOf`, `max`, `min`, `noConflict`, `now`, `pad`, `padLeft`,
* `padRight`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`, `repeat`,
* `result`, `runInContext`, `shift`, `size`, `snakeCase`, `some`, `sortedIndex`,
* `sortedLastIndex`, `startsWith`, `template`, `trim`, `trimLeft`, `trimRight`,
* `trunc`, `unescape`, `uniqueId`, `value`, and `words`
*
* The wrapper function `sample` will return a wrapped value when `n` is
* provided, otherwise it will return an unwrapped value.
*
* Explicit chaining can be enabled by using the `_.chain` method.
*
* @name _
* @constructor
* @category Chain
* @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, n) { return sum + n; });
* // => 6
*
* // returns a wrapped value
* var squares = wrapped.map(function(n) { return n * n; });
*
* _.isArray(squares);
* // => false
*
* _.isArray(squares.value());
* // => true
*/
function lodash(value) {
return (value instanceof lodash)
? value
: new lodashWrapper(value);
}
/**
* A fast path for creating `lodash` wrapper objects.
*
* @private
* @param {*} value The value to wrap in a `lodash` instance.
* @param {boolean} [chainAll=false] Enable chaining for all methods.
* @param {Array} [queue=[]] Actions to peform to resolve the unwrapped value.
* @returns {Object} Returns a `lodash` instance.
*/
function lodashWrapper(value, chainAll) {
this.__chain__ = !!chainAll;
this.__wrapped__ = value;
}
/**
* An object environment feature flags.
*
* @static
* @memberOf _
* @type Object
*/
var support = {};
(function(x) {
var object = { '0': 1, 'length': 1 };
/**
* Detect if `Array#shift` and `Array#splice` augment array-like objects
* correctly.
*
* Firefox < 10, IE compatibility mode, and IE < 9 have buggy Array `shift()`
* and `splice()` functions that fail to remove the last element, `value[0]`,
* of array-like objects even though the `length` property is set to `0`.
* The `shift()` method is buggy in IE 8 compatibility mode, while `splice()`
* is buggy regardless of mode in IE < 9 and buggy in compatibility mode
* in IE 9.
*
* @memberOf _.support
* @type boolean
*/
support.spliceObjects = (splice.call(object, 0, 1), !object[0]);
}(0, 0));
/**
* By default, the template delimiters used by Lo-Dash are similar to those
* in embedded Ruby (ERB). Change the following template settings to use
* alternative delimiters.
*
* @static
* @memberOf _
* @type Object
*/
lodash.templateSettings = {
/**
* Used to detect `data` property values to be HTML-escaped.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'escape': reEscape,
/**
* Used to detect code to be evaluated.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'evaluate': reEvaluate,
/**
* Used to detect `data` property values to inject.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'interpolate': reInterpolate,
/**
* Used to reference the data object in the template text.
*
* @memberOf _.templateSettings
* @type string
*/
'variable': ''
};
/*------------------------------------------------------------------------*/
/**
* The base implementation of `_.assign` without support for argument juggling,
* multiple sources, and `this` binding.
*
* @private
* @param {Object} object The destination object.
* @param {Object} source The source object.
* @param {Function} [customizer] The function to customize assigning values.
* @returns {Object} Returns the destination object.
*/
function baseAssign(object, source, customizer) {
var index = -1,
props = keys(source),
length = props.length;
while (++index < length) {
var key = props[index];
object[key] = customizer
? customizer(object[key], source[key], key, object, source)
: source[key];
}
return object;
}
/**
* The base implementation of `_.bindAll` without support for individual
* method name arguments.
*
* @private
* @param {Object} object The object to bind and assign the bound methods to.
* @param {string[]} methodNames The object method names to bind.
* @returns {Object} Returns `object`.
*/
function baseBindAll(object, methodNames) {
var index = -1,
length = methodNames.length;
while (++index < length) {
var key = methodNames[index];
object[key] = createWrapper(object[key], BIND_FLAG, null, object);
}
return object;
}
/**
* The base implementation of `_.callback` without support for creating
* "_.pluck" and "_.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 the new function.
*/
function baseCallback(func, thisArg, argCount) {
var type = typeof func;
if (type == 'function') {
if (typeof thisArg == 'undefined') {
return func;
}
switch (argCount) {
case 1: return function(value) {
return func.call(thisArg, value);
};
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);
};
case 5: return function(value, other, key, object, source) {
return func.call(thisArg, value, other, key, object, source);
};
}
return function() {
return func.apply(thisArg, arguments);
};
}
if (func == null) {
return identity;
}
// handle "_.pluck" and "_.where" style callback shorthands
return type == 'object' ? matches(func) : property(func);
}
/**
* The base implementation of `_.create` without support for assigning
* properties to the created object.
*
* @private
* @param {Object} prototype The object to inherit from.
* @returns {Object} Returns the new object.
*/
function baseCreate(prototype) {
return isObject(prototype) ? nativeCreate(prototype) : {};
}
// fallback for environments without `Object.create`
if (!nativeCreate) {
baseCreate = (function() {
function Object() {}
return function(prototype) {
if (isObject(prototype)) {
Object.prototype = prototype;
var result = new Object;
Object.prototype = null;
}
return result || root.Object();
};
}());
}
/**
* The base implementation of `_.difference` which accepts a single array
* of values to exclude.
*
* @private
* @param {Array} array The array to inspect.
* @param {Array} values The values to exclude.
* @returns {Array} Returns the new array of filtered values.
*/
function baseDifference(array, values) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
var index = -1,
indexOf = getIndexOf(),
result = [];
while (++index < length) {
var value = array[index];
if (indexOf(values, value) < 0) {
result.push(value);
}
}
return result;
}
/**
* The base implementation of `_.forEach` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array|Object|string} Returns `collection`.
*/
function baseEach(collection, iteratee) {
var length = collection ? collection.length : 0;
if (!(typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER)) {
return baseForOwn(collection, iteratee);
}
var index = -1,
iterable = toObject(collection);
while (++index < length) {
if (iteratee(iterable[index], index, iterable) === BREAK_INDICATOR) {
break;
}
}
return collection;
}
/**
* The base implementation of `_.forEachRight` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array|Object|string} Returns `collection`.
*/
function baseEachRight(collection, iteratee) {
var length = collection ? collection.length : 0;
if (!(typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER)) {
return baseForOwnRight(collection, iteratee);
}
var iterable = toObject(collection);
while (length--) {
if (iteratee(iterable[length], length, iterable) === BREAK_INDICATOR) {
break;
}
}
return collection;
}
/**
* The base implementation of `_.every` without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns `true` if all elements pass the predicate check,
* else `false`
*/
function baseEvery(collection, predicate) {
var result = true;
baseEach(collection, function(value, index, collection) {
result = !!predicate(value, index, collection);
return result || BREAK_INDICATOR;
});
return result;
}
/**
* The base implementation of `_.filter` without support for callback shorthands
* or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns the new filtered array.
*/
function baseFilter(collection, predicate) {
var result = [];
baseEach(collection, function(value, index, collection) {
if (predicate(value, index, collection)) {
result.push(value);
}
});
return result;
}
/**
* The base implementation of `_.find`, `_.findLast`, `_.findKey`, and `_.findLastKey`,
* without support for callback shorthands and `this` binding, which iterates
* over `collection` using the provided `eachFunc`.
*
* @private
* @param {Array|Object|string} collection The collection to search.
* @param {Function} predicate The function invoked per iteration.
* @param {Function} eachFunc The function to iterate over `collection`.
* @param {boolean} [retKey=false] Specify returning the key of the found
* element instead of the element itself.
* @returns {*} Returns the found element or its key, else `undefined`.
*/
function baseFind(collection, predicate, eachFunc, retKey) {
var result;
eachFunc(collection, function(value, key, collection) {
if (predicate(value, key, collection)) {
result = retKey ? key : value;
return BREAK_INDICATOR;
}
});
return result;
}
/**
* The base implementation of `_.flatten` with added support for restricting
* flattening and specifying the start index.
*
* @private
* @param {Array} array The array to flatten.
* @param {boolean} [isDeep=false] Specify a deep flatten.
* @param {boolean} [isStrict=false] Restrict flattening to arrays and `arguments` objects.
* @param {number} [fromIndex=0] The index to start from.
* @returns {Array} Returns the new flattened array.
*/
function baseFlatten(array, isDeep, isStrict, fromIndex) {
var index = (fromIndex || 0) - 1,
length = array.length,
resIndex = -1,
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 (isDeep) {
value = baseFlatten(value, isDeep, isStrict);
}
var valIndex = -1,
valLength = value.length;
result.length += valLength;
while (++valIndex < valLength) {
result[++resIndex] = value[valIndex];
}
} else if (!isStrict) {
result[++resIndex] = value;
}
}
return result;
}
/**
* The base implementation of `baseForIn` and `baseForOwn` which iterates
* over `object` properties returned by `keysFunc` invoking `iteratee` for
* each property. Iterator functions may exit iteration early by explicitly
* returning `false`.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {Function} keysFunc The function to get the keys of `object`.
* @returns {Object} Returns `object`.
*/
function baseFor(object, iteratee, keysFunc) {
var index = -1,
iterable = toObject(object),
props = keysFunc(object),
length = props.length;
while (++index < length) {
var key = props[index];
if (iteratee(iterable[key], key, iterable) === BREAK_INDICATOR) {
break;
}
}
return object;
}
/**
* This function is like `baseFor` except that it iterates over properties
* in the opposite order.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {Function} keysFunc The function to get the keys of `object`.
* @returns {Object} Returns `object`.
*/
function baseForRight(object, iteratee, keysFunc) {
var iterable = toObject(object),
props = keysFunc(object),
length = props.length;
while (length--) {
var key = props[length];
if (iteratee(iterable[key], key, iterable) === BREAK_INDICATOR) {
break;
}
}
return object;
}
/**
* The base implementation of `_.forIn` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForIn(object, iteratee) {
return baseFor(object, iteratee, keysIn);
}
/**
* The base implementation of `_.forOwn` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForOwn(object, iteratee) {
return baseFor(object, iteratee, keys);
}
/**
* The base implementation of `_.forOwnRight` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForOwnRight(object, iteratee) {
return baseForRight(object, iteratee, keys);
}
/**
* The base implementation of `_.functions` which creates an array of
* `object` function property names filtered from those provided.
*
* @private
* @param {Object} object The object to inspect.
* @param {Array} props The property names to filter.
* @returns {Array} Returns the new array of filtered property names.
*/
function baseFunctions(object, props) {
var index = -1,
length = props.length,
resIndex = -1,
result = [];
while (++index < length) {
var key = props[index];
if (isFunction(object[key])) {
result[++resIndex] = key;
}
}
return result;
}
/**
* The base implementation of `_.isEqual`, without support for `thisArg`
* binding, which allows partial "_.where" style comparisons.
*
* @private
* @param {*} value The value to compare to `other`.
* @param {*} other The value to compare to `value`.
* @param {Function} [customizer] The function to customize comparing values.
* @param {boolean} [isWhere=false] Specify performing partial comparisons.
* @param {Array} [stackA=[]] Tracks traversed `value` objects.
* @param {Array} [stackB=[]] Tracks traversed `other` objects.
* @returns {boolean} Returns `true` if the values are equivalent, else `false`.
*/
function baseIsEqual(value, other, stackA, stackB) {
if (value === other) {
return value !== 0 || (1 / value == 1 / other);
}
var valType = typeof value,
othType = typeof other;
if (value === value && (value == null || other == null ||
(valType != 'function' && valType != 'object' && othType != 'function' && othType != 'object'))) {
return false;
}
var valClass = toString.call(value),
othClass = toString.call(other);
if (valClass != othClass) {
return false;
}
switch (valClass) {
case boolClass:
case dateClass:
return +value == +other;
case numberClass:
return value != +value
? other != +other
: (value == 0 ? (1 / value == 1 / other) : value == +other);
case regexpClass:
case stringClass:
return value == String(other);
}
var isArr = arrayLikeClasses[valClass];
if (!isArr) {
if (valClass != objectClass) {
return false;
}
var valWrapped = value instanceof lodash,
othWrapped = other instanceof lodash;
if (valWrapped || othWrapped) {
return baseIsEqual(valWrapped ? value.__wrapped__ : value, othWrapped ? other.__wrapped__ : other, stackA, stackB);
}
var hasValCtor = hasOwnProperty.call(value, 'constructor'),
hasOthCtor = hasOwnProperty.call(other, 'constructor');
if (hasValCtor != hasOthCtor) {
return false;
}
if (!hasValCtor) {
var valCtor = value.constructor,
othCtor = other.constructor;
if (valCtor != othCtor && ('constructor' in value && 'constructor' in other) &&
!(typeof valCtor == 'function' && valCtor instanceof valCtor &&
typeof othCtor == 'function' && othCtor instanceof othCtor)) {
return false;
}
}
}
stackA || (stackA = []);
stackB || (stackB = []);
var length = stackA.length;
while (length--) {
if (stackA[length] == value) {
return stackB[length] == other;
}
}
stackA.push(value);
stackB.push(other);
if (isArr) {
length = value.length;
var result = length == other.length;
if (result) {
while (length--) {
result = baseIsEqual(value[length], other[length], stackA, stackB);
if (!result) {
break;
}
}
}
}
else {
var props = keys(value);
length = props.length;
result = length == keys(other).length;
if (result) {
while (length--) {
var key = props[length];
result = hasOwnProperty.call(other, key) && baseIsEqual(value[key], other[key], stackA, stackB);
if (!result) {
break;
}
}
}
}
stackA.pop();
stackB.pop();
return result;
}
/**
* The base implementation of `_.invoke` which requires additional arguments
* be provided as an array of arguments rather than individually.
*
* @private
* @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 {Array} [args] The arguments to invoke the method with.
* @returns {Array} Returns the array of results.
*/
function baseInvoke(collection, methodName, args) {
var index = -1,
isFunc = typeof methodName == 'function',
length = collection ? collection.length : 0,
result = [];
if (typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER) {
result.length = length;
}
baseEach(collection, function(value) {
var func = isFunc ? methodName : (value != null && value[methodName]);
result[++index] = func ? func.apply(value, args) : undefined;
});
return result;
}
/**
* The base implementation of `_.map` without support for callback shorthands
* or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns the new mapped array.
*/
function baseMap(collection, iteratee) {
var result = [];
baseEach(collection, function(value, key, collection) {
result.push(iteratee(value, key, collection));
});
return result;
}
/**
* The base implementation of `_.partial` and `_.partialRight` which accepts
* an array of arguments to partially apply and handles resolving the arity
* of `func`.
*
* @private
* @param {Function} func The function to partially apply arguments to.
* @param {number} bitmask The bitmask of flags to compose.
* @param {Array} args The arguments to be partially applied.
* @param {*} [thisArg] The `this` binding of `func`.
* @returns {Function} Returns the new partially applied function.
*/
function basePartial(func, bitmask, args, holders, thisArg) {
if (func) {
var arity = func.length;
arity = nativeMax(arity - args.length, 0);
}
return (bitmask & PARTIAL_FLAG)
? createWrapper(func, bitmask, arity, thisArg, args, holders)
: createWrapper(func, bitmask, arity, thisArg, null, null, args, holders);
}
/**
* The base implementation of `_.random` without support for argument juggling
* and returning floating-point numbers.
*
* @private
* @param {number} min The minimum possible value.
* @param {number} max The maximum possible value.
* @returns {number} Returns the random number.
*/
function baseRandom(min, max) {
return min + floor(nativeRandom() * (max - min + 1));
}
/**
* The base implementation of `_.reduce` and `_.reduceRight` without support
* for callback shorthands or `this` binding, which iterates over `collection`
* usingthe provided `eachFunc`.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} accumulator The initial value.
* @param {boolean} initFromCollection Specify using the first or last element
* of `collection` as the initial value.
* @param {Function} eachFunc The function to iterate over `collection`.
* @returns {*} Returns the accumulated value.
*/
function baseReduce(collection, iteratee, accumulator, initFromCollection, eachFunc) {
eachFunc(collection, function(value, index, collection) {
accumulator = initFromCollection
? (initFromCollection = false, value)
: iteratee(accumulator, value, index, collection)
});
return accumulator;
}
/**
* The base implementation of `_.some` without support for callback shorthands
* or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
*/
function baseSome(collection, predicate) {
var result;
baseEach(collection, function(value, index, collection) {
result = predicate(value, index, collection);
return result && BREAK_INDICATOR;
});
return !!result;
}
/**
* The base implementation of `_.sortedIndex` and `_.sortedLastIndex` without
* support for callback shorthands and `this` binding.
*
* @private
* @param {Array} array The array to inspect.
* @param {*} value The value to evaluate.
* @param {Function} iteratee The function invoked per iteration.
* @param {boolean} [retHighest=false] Specify returning the highest, instead
* of the lowest, index at which a value should be inserted into `array`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
*/
function baseSortedIndex(array, value, iteratee, retHighest) {
var low = 0,
high = array ? array.length : low;
value = iteratee(value);
var valIsNaN = value !== value,
valIsUndef = typeof value == 'undefined';
while (low < high) {
var mid = floor((low + high) / 2),
computed = iteratee(array[mid]),
isReflexive = computed === computed;
if (valIsNaN) {
var setLow = isReflexive || retHighest;
} else if (valIsUndef) {
setLow = isReflexive && (retHighest || typeof computed != 'undefined');
} else {
setLow = retHighest ? (computed <= value) : (computed < value);
}
if (setLow) {
low = mid + 1;
} else {
high = mid;
}
}
return nativeMin(high, MAX_ARRAY_INDEX);
}
/**
* The base implementation of `_.uniq` without support for callback shorthands
* and `this` binding.
*
* @private
* @param {Array} array The array to inspect.
* @param {Function} [iteratee] The function invoked per iteration.
* @returns {Array} Returns the new duplicate-value-free array.
*/
function baseUniq(array, iteratee) {
var index = -1,
indexOf = getIndexOf(),
length = array.length,
result = [],
seen = iteratee ? [] : result;
while (++index < length) {
var value = array[index],
computed = iteratee ? iteratee(value, index, array) : value;
if (indexOf(seen, computed) < 0) {
if (iteratee) {
seen.push(computed);
}
result.push(value);
}
}
return result;
}
/**
* The base implementation of `_.values` and `_.valuesIn` which creates an
* array of `object` property values corresponding to the property names
* returned by `keysFunc`.
*
* @private
* @param {Object} object The object to inspect.
* @param {Function} keysFunc The function to get the keys of `object`.
* @returns {Object} Returns the array of property values.
*/
function baseValues(object, keysFunc) {
var index = -1,
props = keysFunc(object),
length = props.length,
result = Array(length);
while (++index < length) {
result[index] = object[props[index]];
}
return result;
}
/**
* Creates an array that is the composition of partially applied arguments,
* placeholders, and provided arguments into a single array of arguments.
*
* @private
* @param {Array} partialArgs The arguments to prepend to those provided.
* @param {Array} partialHolders The `partialArgs` placeholder indexes.
* @param {Array|Object} args The provided arguments.
* @returns {Array} Returns the new array of composed arguments.
*/
function composeArgs(partialArgs, partialHolders, args) {
var holdersLength = partialHolders.length,
argsIndex = -1,
argsLength = nativeMax(args.length - holdersLength, 0),
leftIndex = -1,
leftLength = partialArgs.length,
result = Array(argsLength + leftLength);
while (++leftIndex < leftLength) {
result[leftIndex] = partialArgs[leftIndex];
}
while (++argsIndex < holdersLength) {
result[partialHolders[argsIndex]] = args[argsIndex];
}
while (argsLength--) {
result[leftIndex++] = args[argsIndex++];
}
return result;
}
/**
* Creates a function that aggregates a collection, creating an accumulator
* object composed from the results of running each element in the collection
* through `iteratee`. The given setter function sets the keys and values of
* the accumulator object. If `initializer` is provided it is used to initialize
* the accumulator object.
*
* @private
* @param {Function} setter The function to set keys and values of the accumulator object.
* @param {Function} [initializer] The function to initialize the accumulator object.
* @returns {Function} Returns the new aggregator function.
*/
function createAggregator(setter, initializer) {
return function(collection, iteratee, thisArg) {
iteratee = baseCallback(iteratee, thisArg, 3);
var result = initializer ? initializer() : {};
if (isArray(collection)) {
var index = -1,
length = collection.length;
while (++index < length) {
var value = collection[index];
setter(result, value, iteratee(value, index, collection), collection);
}
} else {
baseEach(collection, function(value, key, collection) {
setter(result, value, iteratee(value, key, collection), collection);
});
}
return result;
};
}
/**
* Creates a function that wraps `func` and invokes it with the `this`
* binding of `thisArg`.
*
* @private
* @param {Function} func The function to bind.
* @param {*} [thisArg] The `this` binding of `func`.
* @returns {Function} Returns the new wrapped function.
*/
function createBindWrapper(func, thisArg) {
var Ctor = createCtorWrapper(func);
function wrapper() {
return (this instanceof wrapper ? Ctor : func).apply(thisArg, arguments);
}
return wrapper;
}
/**
* Creates a function that produces an instance of `Ctor` regardless of
* whether it was invoked as part of a `new` expression or by `call` or `apply`.
*
* @private
* @param {Function} Ctor The constructor to wrap.
* @returns {Function} Returns the new function.
*/
function createCtorWrapper(Ctor) {
return function() {
var thisBinding = baseCreate(Ctor.prototype),
result = Ctor.apply(thisBinding, arguments);
// mimic the constructor's `return` behavior
// http://es5.github.io/#x13.2.2
return isObject(result) ? result : thisBinding;
};
}
/**
* Creates a function that wraps `func` and invokes it with optional `this`
* binding of, partial application, and currying.
*
* @private
* @param {Function|string} func The function or method name to reference.
* @param {number} bitmask The bitmask of flags. See `createWrapper` for more details.
* @param {number} arity The arity of `func`.
* @param {*} [thisArg] The `this` binding of `func`.
* @param {Array} [partialArgs] The arguments to prepend to those provided to the new function.
* @param {Array} [partialHolders] The `partialArgs` placeholder indexes.
* @param {Array} [partialRightArgs] The arguments to append to those provided to the new function.
* @param {Array} [partialRightHolders] The `partialRightArgs` placeholder indexes.
* @returns {Function} Returns the new function.
*/
function createHybridWrapper(func, bitmask, arity, thisArg, partialArgs, partialHolders, partialRightArgs, partialRightHolders) {
var isBind = bitmask & BIND_FLAG,
isBindKey = bitmask & BIND_KEY_FLAG,
isCurry = bitmask & CURRY_FLAG,
isCurryRight = bitmask & CURRY_RIGHT_FLAG,
isCurryBound = bitmask & CURRY_BOUND_FLAG;
var Ctor = !isBindKey && createCtorWrapper(func),
key = func;
function wrapper() {
var length = arguments.length,
index = length,
args = Array(length);
while (index--) {
args[index] = arguments[index];
}
if (partialArgs) {
args = composeArgs(partialArgs, partialHolders, args);
}
var thisBinding = isBind ? thisArg : this;
return (this instanceof wrapper ? (Ctor || createCtorWrapper(func)) : func).apply(thisBinding, args);
}
return wrapper;
}
/**
* Creates a function that wraps `func` and invokes it with the optional `this`
* binding of `thisArg` and the `partialArgs` prepended to those provided to
* the wrapper.
*
* @private
* @param {Function} func The function to partially apply arguments to.
* @param {number} bitmask The bitmask of flags. See `createWrapper` for more details.
* @param {Array} partialArgs The arguments to prepend to those provided to the new function.
* @param {*} [thisArg] The `this` binding of `func`.
* @returns {Function} Returns the new bound function.
*/
function createPartialWrapper(func, bitmask, partialArgs, thisArg) {
var isBind = bitmask & BIND_FLAG,
Ctor = createCtorWrapper(func);
function wrapper() {
// avoid `arguments` object use disqualifying optimizations by
// converting it to an array before passing it to `composeArgs`
var argsIndex = -1,
argsLength = arguments.length,
leftIndex = -1,
leftLength = partialArgs.length,
args = Array(argsLength + leftLength);
while (++leftIndex < leftLength) {
args[leftIndex] = partialArgs[leftIndex];
}
while (argsLength--) {
args[leftIndex++] = arguments[++argsIndex];
}
return (this instanceof wrapper ? Ctor : func).apply(isBind ? thisArg : this, args);
}
return wrapper;
}
/**
* Creates a function that either curries or invokes `func` with optional
* `this` binding and partially applied arguments.
*
* @private
* @param {Function|string} func The function or method name to reference.
* @param {number} bitmask The bitmask of flags.
* The bitmask may be composed of the following flags:
* 1 - `_.bind`
* 2 - `_.bindKey`
* 4 - `_.curry`
* 8 - `_.curryRight`
* 16 - `_.curry` or `_.curryRight` of a bound function
* 32 - `_.partial`
* 64 - `_.partialRight`
* @param {number} arity The arity of `func`.
* @param {*} [thisArg] The `this` binding of `func`.
* @param {Array} [partialArgs] The arguments to prepend to those provided to the new function.
* @param {Array} [partialHolders] The `partialArgs` placeholder indexes.
* @param {Array} [partialRightArgs] The arguments to append to those provided to the new function.
* @param {Array} [partialRightHolders] The `partialRightArgs` placeholder indexes.
* @returns {Function} Returns the new function.
*/
function createWrapper(func, bitmask, arity, thisArg, partialArgs, partialHolders, partialRightArgs, partialRightHolders) {
var isBindKey = bitmask & BIND_KEY_FLAG;
if (!isFunction(func)) {
throw new TypeError(FUNC_ERROR_TEXT);
}
var isPartial = bitmask & PARTIAL_FLAG;
if (isPartial && !partialArgs.length) {
bitmask &= ~PARTIAL_FLAG;
isPartial = false;
partialArgs = partialHolders = null;
}
if (arity == null) {
arity = func.length;
}
if (bitmask == BIND_FLAG) {
var result = createBindWrapper(func, thisArg);
} else if ((bitmask == PARTIAL_FLAG || bitmask == (BIND_FLAG | PARTIAL_FLAG)) && !partialHolders.length) {
result = createPartialWrapper(func, bitmask, partialArgs, thisArg);
} else {
result = createHybridWrapper(func, bitmask, arity, thisArg, partialArgs, partialHolders, partialRightArgs, partialRightHolders);
}
return result;
}
/**
* Gets the appropriate "indexOf" function. If the `_.indexOf` method is
* customized this function returns the custom method, otherwise it returns
* the `baseIndexOf` function. If arguments are provided the chosen function
* is invoked with them and its result is returned.
*
* @private
* @returns {Function|number} Returns the chosen function or its result.
*/
function getIndexOf(collection, target, fromIndex) {
var result = lodash.indexOf || indexOf;
result = result === indexOf ? baseIndexOf : result;
return collection ? result(collection, target, fromIndex) : result;
}
/**
* A specialized version of `_.pick` that picks `object` properties
* specified by the `props` array.
*
* @private
* @param {Object} object The source object.
* @param {string[]} props The property names to pick.
* @returns {Object} Returns the new object.
*/
function pickByArray(object, props) {
object = toObject(object);
var index = -1,
length = props.length,
result = {};
while (++index < length) {
var key = props[index];
if (key in object) {
result[key] = object[key];
}
}
return result;
}
/**
* A specialized version of `_.pick` that picks `object` properties `predicate`
* returns truthy for.
*
* @private
* @param {Object} object The source object.
* @param {Function} predicate The function invoked per iteration.
* @returns {Object} Returns the new object.
*/
function pickByCallback(object, predicate) {
var result = {};
baseForIn(object, function(value, key, object) {
if (predicate(value, key, object)) {
result[key] = value;
}
});
return result;
}
/**
* A fallback implementation of `Object.keys` which creates an array of the
* own enumerable property names of `object`.
*
* @private
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
*/
function shimKeys(object) {
var index = -1,
props = keysIn(object),
length = props.length,
result = [];
while (++index < length) {
var key = props[index];
if (hasOwnProperty.call(object, key)) {
result.push(key);
}
}
return result;
}
/**
* Converts `value` to an array-like object if it is not one.
*
* @private
* @param {*} value The value to process.
* @returns {Array|Object} Returns the array-like object.
*/
function toIterable(value) {
if (value == null) {
return [];
}
var length = value.length;
if (!(typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER)) {
return values(value);
}
return isObject(value) ? value : Object(value);
}
/**
* Converts `value` to an object if it is not one.
*
* @private
* @param {*} value The value to process.
* @returns {Object} Returns the object.
*/
function toObject(value) {
return isObject(value) ? value : Object(value);
}
/*------------------------------------------------------------------------*/
/**
* Creates an array with all falsey values removed. The values `false`, `null`,
* `0`, `""`, `undefined`, and `NaN` are all falsey.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to compact.
* @returns {Array} Returns the new array of filtered values.
* @example
*
* _.compact([0, 1, false, 2, '', 3]);
* // => [1, 2, 3]
*/
function compact(array) {
var index = -1,
length = array ? array.length : 0,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index];
if (value) {
result[++resIndex] = value;
}
}
return result;
}
/**
* Creates an array excluding all values of the provided arrays using
* `SameValueZero` for equality comparisons.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to inspect.
* @param {...Array} [values] The arrays of values to exclude.
* @returns {Array} Returns the new array of filtered values.
* @example
*
* _.difference([1, 2, 3], [5, 2, 10]);
* // => [1, 3]
*/
function difference() {
var index = -1,
length = arguments.length;
while (++index < length) {
var value = arguments[index];
if (isArray(value) || isArguments(value)) {
break;
}
}
return baseDifference(arguments[index], baseFlatten(arguments, false, true, ++index));
}
/**
* Creates a slice of `array` with `n` elements dropped from the beginning.
*
* @static
* @memberOf _
* @type Function
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to drop.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.drop([1, 2, 3], 1);
* // => [2, 3]
*
* _.drop([1, 2, 3], 2);
* // => [3]
*
* _.drop([1, 2, 3], 5);
* // => []
*
* _.drop([1, 2, 3], 0);
* // => [1, 2, 3]
*/
var drop = rest;
/**
* This method is like `_.find` except that it returns the index of the first
* element `predicate` returns truthy for, instead of the element itself.
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {number} Returns the index of the found element, else `-1`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true },
* { 'user': 'pebbles', 'age': 1 }
* ];
*
* _.findIndex(users, function(chr) {
* return chr.age < 20;
* });
* // => 2
*
* // using "_.where" callback shorthand
* _.findIndex(users, { 'age': 36 });
* // => 0
*
* // using "_.pluck" callback shorthand
* _.findIndex(users, 'blocked');
* // => 1
*/
function findIndex(array, predicate, thisArg) {
var index = -1,
length = array ? array.length : 0;
predicate = baseCallback(predicate, thisArg, 3);
while (++index < length) {
if (predicate(array[index], index, array)) {
return index;
}
}
return -1;
}
/**
* Gets the first element of `array`.
*
* @static
* @memberOf _
* @alias head
* @category Array
* @param {Array} array The array to query.
* @returns {*} Returns the first element of `array`.
* @example
*
* _.first([1, 2, 3]);
* // => 1
*
* _.first([]);
* // => undefined
*/
function first(array, n, guard) {
if (n == null || guard) {
return array ? array[0] : undefined;
}
return slice(array, 0, n < 0 ? 0 : n);
}
/**
* Flattens a nested array. If `isDeep` is `true` the array is recursively
* flattened, otherwise it is only flattened a single level.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to flatten.
* @param {boolean} [isDeep=false] Specify a deep flatten.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the new flattened array.
* @example
*
* _.flatten([1, [2], [3, [[4]]]]);
* // => [1, 2, 3, [[4]]];
*
* // using `isDeep`
* _.flatten([1, [2], [3, [[4]]]], true);
* // => [1, 2, 3, 4];
*/
function flatten(array, isDeep, guard) {
var length = array ? array.length : 0;
return length ? baseFlatten(array, guard ? true : !isDeep) : [];
}
/**
* Gets the index at which the first occurrence of `value` is found in `array`
* using `SameValueZero` for equality comparisons. If `fromIndex` is negative,
* it is used as the offset from the end of the collection. If `array` is
* sorted providing `true` for `fromIndex` performs a faster binary search.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @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, else `-1`.
* @example
*
* _.indexOf([1, 2, 3, 1, 2, 3], 2);
* // => 1
*
* // using `fromIndex`
* _.indexOf([1, 2, 3, 1, 2, 3], 2, 3);
* // => 4
*
* // performing a binary search
* _.indexOf([4, 4, 5, 5, 6, 6], 5, true);
* // => 2
*/
function indexOf(array, value, fromIndex) {
var length = array ? array.length : 0;
if (!length) {
return -1;
}
if (typeof fromIndex == 'number') {
fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (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 of `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.initial([1, 2, 3]);
* // => [1, 2]
*/
function initial(array, n, guard) {
var length = array ? array.length : 0;
if (n == null || guard) {
n = 1;
}
n = length - (n || 0);
return slice(array, 0, n < 0 ? 0 : n);
}
/**
* Creates an array of unique values present in all provided arrays using
* `SameValueZero` for equality comparisons.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new 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);
}
}
argsLength = args.length;
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 of `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @returns {*} Returns the last element of `array`.
* @example
*
* _.last([1, 2, 3]);
* // => 3
*/
function last(array, n, guard) {
var length = array ? array.length : 0;
if (n == null || guard) {
return array ? array[length - 1] : undefined;
}
n = length - (n || 0);
return slice(array, n < 0 ? 0 : n);
}
/**
* This method is like `_.indexOf` except that it iterates over elements of
* `array` from right to left.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {*} value The value to search for.
* @param {boolean|number} [fromIndex=array.length-1] 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, else `-1`.
* @example
*
* _.lastIndexOf([1, 2, 3, 1, 2, 3], 2);
* // => 4
*
* // using `fromIndex`
* _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3);
* // => 1
*
* // performing a binary search
* _.lastIndexOf([4, 4, 5, 5, 6, 6], 5, true);
* // => 3
*/
function lastIndexOf(array, value, fromIndex) {
var length = array ? array.length : 0;
if (!length) {
return -1;
}
var index = length;
if (typeof fromIndex == 'number') {
index = (fromIndex < 0 ? nativeMax(length + fromIndex, 0) : nativeMin(fromIndex || 0, length - 1)) + 1;
}
if (value !== value) {
return indexOfNaN(array, index, true);
}
while (index--) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* Gets all but the first element of `array`.
*
* @static
* @memberOf _
* @alias tail
* @category Array
* @param {Array} array The array to query.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.rest([1, 2, 3]);
* // => [2, 3]
*/
function rest(array, n, guard) {
if (n == null || guard) {
n = 1;
} else {
n = n < 0 ? 0 : n;
}
return slice(array, n);
}
/**
* Slices `array` from the `start` index up to, but not including, the `end` index.
*
* **Note:** This function is used instead of `Array#slice` to support node lists
* in IE < 9 and to ensure dense arrays are returned.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to slice.
* @param {number} [start=0] The start index.
* @param {number} [end=array.length] The end index.
* @returns {Array} Returns the slice of `array`.
*/
function slice(array, start, end) {
var index = -1,
length = array ? array.length : 0,
endType = typeof end;
if (end && endType != 'number' && isIterateeCall(array, start, end)) {
start = 0;
end = length;
}
start = start == null ? 0 : (+start || 0);
if (start < 0) {
start = -start > length ? 0 : (length + start);
}
end = (endType == 'undefined' || end > length) ? length : (+end || 0);
if (end < 0) {
end += length;
}
if (end && end == length && !start) {
return baseSlice(array);
}
length = start > end ? 0 : (end - start);
var result = Array(length);
while (++index < length) {
result[index] = array[index + start];
}
return result;
}
/**
* Uses a binary search to determine the lowest index at which a value should
* be inserted into a given sorted array in order to maintain the sort order
* of the array. If an iteratee function is provided it is invoked for `value`
* and each element of `array` to compute their sort ranking. The iteratee
* is bound to `thisArg` and invoked with one argument; (value).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to inspect.
* @param {*} value The value to evaluate.
* @param {Function|Object|string} [iteratee=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
* @example
*
* _.sortedIndex([30, 50], 40);
* // => 1
*
* _.sortedIndex([4, 4, 5, 5, 6, 6], 5);
* // => 2
*
* var dict = { 'data': { 'thirty': 30, 'forty': 40, 'fifty': 50 } };
*
* // using an iteratee function
* _.sortedIndex(['thirty', 'fifty'], 'forty', function(word) {
* return this.data[word];
* }, dict);
* // => 1
*
* // using "_.pluck" callback shorthand
* _.sortedIndex([{ 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
* // => 1
*/
function sortedIndex(array, value, iteratee, thisArg) {
iteratee = iteratee == null ? identity : baseCallback(iteratee, thisArg, 1);
return baseSortedIndex(array, value, iteratee);
}
/**
* Creates a slice of `array` with `n` elements taken from the beginning.
*
* @static
* @memberOf _
* @type Function
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to take.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.take([1, 2, 3], 1);
* // => [1]
*
* _.take([1, 2, 3], 2);
* // => [1, 2]
*
* _.take([1, 2, 3], 5);
* // => [1, 2, 3]
*
* _.take([1, 2, 3], 0);
* // => []
*/
var take = first;
/**
* Creates an array of unique values, in order, of the provided arrays using
* `SameValueZero` for equality comparisons.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new 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, false, true));
}
/**
* Creates a duplicate-value-free version of an array using `SameValueZero`
* for equality comparisons. Providing `true` for `isSorted` performs a faster
* search algorithm for sorted arrays. If an iteratee function is provided it
* is invoked for each value in the array to generate the criterion by which
* uniqueness is computed. The `iteratee` is bound to `thisArg` and invoked
* with three arguments; (value, index, array).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @alias unique
* @category Array
* @param {Array} array The array to inspect.
* @param {boolean} [isSorted=false] Specify the array is sorted.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.pluck"
* or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new duplicate-value-free array.
* @example
*
* _.uniq([1, 2, 1]);
* // => [1, 2]
*
* // using `isSorted`
* _.uniq([1, 1, 2], true);
* // => [1, 2]
*
* // using an iteratee function
* _.uniq([1, 2.5, 1.5, 2], function(n) { return this.floor(n); }, Math);
* // => [1, 2.5]
*
* // using "_.pluck" callback shorthand
* _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
* // => [{ 'x': 1 }, { 'x': 2 }]
*/
function uniq(array, isSorted, iteratee, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
// juggle arguments
if (typeof isSorted != 'boolean' && isSorted != null) {
thisArg = iteratee;
iteratee = isIterateeCall(array, isSorted, thisArg) ? null : isSorted;
isSorted = false;
}
if (iteratee != null) {
iteratee = baseCallback(iteratee, thisArg, 3);
}
return (isSorted && getIndexOf() == baseIndexOf)
? sortedUniq(array, iteratee)
: baseUniq(array, iteratee);
}
/**
* This method is like `_.zip` except that it accepts an array of grouped
* elements and creates an array regrouping the elements to their pre `_.zip`
* configuration.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array of grouped elements to process.
* @returns {Array} Returns the new array of regrouped elements.
* @example
*
* var zipped = _.zip(['fred', 'barney'], [30, 40], [true, false]);
* // => [['fred', 30, true], ['barney', 40, false]]
*
* _.unzip(zipped);
* // => [['fred', 'barney'], [30, 40], [true, false]]
*/
function unzip(array) {
var index = -1,
length = isObject(length = max(array, 'length')) && length.length || 0,
result = Array(length);
while (++index < length) {
result[index] = pluck(array, index);
}
return result;
}
/**
* Creates an array excluding all provided values using `SameValueZero` for
* equality comparisons.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to filter.
* @param {...*} [values] The values to exclude.
* @returns {Array} Returns the 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 _
* @category Array
* @param {...Array} [arrays] The arrays to process.
* @returns {Array} Returns the new array of grouped elements.
* @example
*
* _.zip(['fred', 'barney'], [30, 40], [true, false]);
* // => [['fred', 30, true], ['barney', 40, false]]
*/
function zip() {
var length = arguments.length,
array = Array(length);
while (length--) {
array[length] = arguments[length];
}
return unzip(array);
}
/**
* Creates an object composed from arrays of property names and values. Provide
* either a single two dimensional array, e.g. `[[key1, value1], [key2, value2]]`
* or two arrays, one of property names and one of corresponding values.
*
* @static
* @memberOf _
* @alias object
* @category Array
* @param {Array} props The property names.
* @param {Array} [vals=[]] The property values.
* @returns {Object} Returns the new object.
* @example
*
* _.zipObject(['fred', 'barney'], [30, 40]);
* // => { 'fred': 30, 'barney': 40 }
*/
function zipObject(props, vals) {
var index = -1,
length = props ? props.length : 0,
result = {};
if (!vals && length && !isArray(props[0])) {
vals = [];
}
while (++index < length) {
var key = props[index];
if (vals) {
result[key] = vals[index];
} else if (key) {
result[key[0]] = key[1];
}
}
return result;
}
/*------------------------------------------------------------------------*/
/**
* Creates a `lodash` object that wraps `value` with explicit method
* chaining enabled.
*
* @static
* @memberOf _
* @category Chain
* @param {*} value The value to wrap.
* @returns {Object} Returns the new wrapper object.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 },
* { 'user': 'pebbles', 'age': 1 }
* ];
*
* var youngest = _.chain(users)
* .sortBy('age')
* .map(function(chr) { return chr.user + ' is ' + chr.age; })
* .first()
* .value();
* // => 'pebbles is 1'
*/
function chain(value) {
var result = lodash(value);
result.__chain__ = true;
return result;
}
/**
* This method invokes `interceptor` and returns `value`. The interceptor is
* bound to `thisArg` and invoked with one argument; (value). The purpose of
* this method is to "tap into" a method chain in order to perform operations
* on intermediate results within the chain.
*
* @static
* @memberOf _
* @category Chain
* @param {*} value The value to provide to `interceptor`.
* @param {Function} interceptor The function to invoke.
* @param {*} [thisArg] The `this` binding of `interceptor`.
* @returns {*} Returns `value`.
* @example
*
* _([1, 2, 3])
* .tap(function(array) { array.pop(); })
* .reverse()
* .value();
* // => [2, 1]
*/
function tap(value, interceptor) {
interceptor(value);
return value;
}
/**
* Enables explicit method chaining on the wrapper object.
*
* @name chain
* @memberOf _
* @category Chain
* @returns {*} Returns the wrapper object.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* // without explicit chaining
* _(users).first();
* // => { 'user': 'barney', 'age': 36 }
*
* // with explicit chaining
* _(users).chain()
* .first()
* .pick('age')
* .value();
* // => { 'age': 36 }
*/
function wrapperChain() {
return chain(this);
}
/**
* Extracts the unwrapped value from its wrapper.
*
* @name valueOf
* @memberOf _
* @alias toJSON, value
* @category Chain
* @returns {*} Returns the unwrapped value.
* @example
*
* _([1, 2, 3]).valueOf();
* // => [1, 2, 3]
*/
function wrapperValueOf() {
return this.__wrapped__;
}
/*------------------------------------------------------------------------*/
/**
* Checks if `value` is present in `collection` using `SameValueZero` for
* equality comparisons. If `fromIndex` is negative, it is used as the offset
* from the end of the collection.
*
* **Note:** `SameValueZero` is like strict equality, e.g. `===`, except that
* `NaN` matches `NaN`. See the [ES6 spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @alias include
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {*} target The value to check for.
* @param {number} [fromIndex=0] The index to search from.
* @returns {boolean} Returns `true` if a matching element is found, else `false`.
* @example
*
* _.contains([1, 2, 3], 1);
* // => true
*
* _.contains([1, 2, 3], 1, 2);
* // => false
*
* _.contains({ 'user': 'fred', 'age': 40 }, 'fred');
* // => true
*
* _.contains('pebbles', 'eb');
* // => true
*/
function contains(collection, target) {
var length = collection ? collection.length : 0;
if (!(typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER)) {
collection = values(collection);
length = collection.length;
}
return length ? (getIndexOf(collection, target) > -1) : false;
}
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` through `iteratee`. The corresponding value
* of each key is the number of times the key was returned by `iteratee`.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* _.countBy([4.3, 6.1, 6.4], function(n) { return Math.floor(n); });
* // => { '4': 1, '6': 2 }
*
* _.countBy([4.3, 6.1, 6.4], function(n) { return this.floor(n); }, 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 `predicate` returns truthy for **all** elements of `collection`.
* The predicate is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias all
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {boolean} Returns `true` if all elements pass the predicate check,
* else `false`.
* @example
*
* _.every([true, 1, null, 'yes']);
* // => false
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* // using "_.pluck" callback shorthand
* _.every(users, 'age');
* // => true
*
* // using "_.where" callback shorthand
* _.every(users, { 'age': 36 });
* // => false
*/
function every(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayEvery : baseEvery;
if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
predicate = baseCallback(predicate, thisArg, 3);
}
return func(collection, predicate);
}
/**
* Iterates over elements of `collection`, returning an array of all elements
* `predicate` returns truthy for. The predicate is bound to `thisArg` and
* invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias select
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the new filtered array.
* @example
*
* var evens = _.filter([1, 2, 3, 4], function(n) { return n % 2 == 0; });
* // => [2, 4]
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true }
* ];
*
* // using "_.pluck" callback shorthand
* _.filter(users, 'blocked');
* // => [{ 'user': 'fred', 'age': 40, 'blocked': true }]
*
* // using "_.where" callback shorthand
* _.filter(users, { 'age': 36 });
* // => [{ 'user': 'barney', 'age': 36 }]
*/
function filter(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayFilter : baseFilter;
predicate = baseCallback(predicate, thisArg, 3);
return func(collection, predicate);
}
/**
* Iterates over elements of `collection`, returning the first element
* `predicate` returns truthy for. The predicate is bound to `thisArg` and
* invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias detect
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {*} Returns the matched element, else `undefined`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true },
* { 'user': 'pebbles', 'age': 1 }
* ];
*
* _.find(users, function(chr) {
* return chr.age < 40;
* });
* // => { 'user': 'barney', 'age': 36 }
*
* // using "_.where" callback shorthand
* _.find(users, { 'age': 1 });
* // => { 'user': 'pebbles', 'age': 1 }
*
* // using "_.pluck" callback shorthand
* _.find(users, 'blocked');
* // => { 'user': 'fred', 'age': 40, 'blocked': true }
*/
function find(collection, predicate, thisArg) {
if (isArray(collection)) {
var index = findIndex(collection, predicate, thisArg);
return index > -1 ? collection[index] : undefined;
}
predicate = baseCallback(predicate, thisArg, 3);
return baseFind(collection, predicate, baseEach);
}
/**
* Performs a deep comparison between each element in `collection` and the
* source object, returning the first element that has equivalent property
* values.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Object} source The object of property values to match.
* @returns {*} Returns the matched element, else `undefined`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'employer': 'slate' },
* { 'user': 'fred', 'age': 40, 'employer': 'slate' }
* ];
*
* _.findWhere(users, { 'employer': 'slate' });
* // => { 'user': 'barney', 'age': 36, 'employer': 'slate' }
*
* _.findWhere(users, { 'age': 40 });
* // => { 'user': 'fred', 'age': 40, 'employer': 'slate' }
*/
function findWhere(collection, source) {
return find(collection, matches(source));
}
/**
* Iterates over elements of `collection` invoking `iteratee` for each element.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection). Iterator functions 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 Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array|Object|string} Returns `collection`.
* @example
*
* _([1, 2, 3]).forEach(function(n) { console.log(n); });
* // => logs each value from left to right and returns the array
*
* _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, function(n, key) { console.log(n, key); });
* // => logs each value-key pair and returns the object (iteration order is not guaranteed)
*/
function forEach(collection, iteratee, thisArg) {
return (typeof iteratee == 'function' && typeof thisArg == 'undefined' && isArray(collection))
? arrayEach(collection, iteratee)
: baseEach(collection, baseCallback(iteratee, thisArg, 3));
}
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` through `iteratee`. The corresponding
* value of each key is an array of the elements responsible for generating
* the key. The `iteratee` is bound to `thisArg` and invoked with three
* arguments; (value, index|key, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* _.groupBy([4.2, 6.1, 6.4], function(n) { return Math.floor(n); });
* // => { '4': [4.2], '6': [6.1, 6.4] }
*
* _.groupBy([4.2, 6.1, 6.4], function(n) { return this.floor(n); }, Math);
* // => { '4': [4.2], '6': [6.1, 6.4] }
*
* // using "_.pluck" callback shorthand
* _.groupBy(['one', 'two', 'three'], 'length');
* // => { '3': ['one', 'two'], '5': ['three'] }
*/
var groupBy = createAggregator(function(result, value, key) {
if (hasOwnProperty.call(result, key)) {
result[key].push(value);
} else {
result[key] = [value];
}
});
/**
* Creates an object composed of keys generated from the results of running
* each element of the collection through `iteratee`. The corresponding value
* of each key is the last element responsible for generating the key. The
* iteratee function is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* var keyData = [
* { 'dir': 'left', 'code': 97 },
* { 'dir': 'right', 'code': 100 }
* ];
*
* _.indexBy(keyData, 'dir');
* // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
*
* _.indexBy(keyData, function(object) { return String.fromCharCode(object.code); });
* // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
*
* _.indexBy(keyData, function(object) { return this.fromCharCode(object.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. Any additional
* arguments are provided to each invoked method. If `methodName` is a function
* it is invoked for, and `this` bound to, each element in the collection.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|string} methodName The name of the method to invoke or
* the function invoked per iteration.
* @param {...*} [args] The arguments to invoke the method with.
* @returns {Array} Returns the array of results.
* @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) {
return baseInvoke(collection, methodName, slice(arguments, 2));
}
/**
* Creates an array of values by running each element in the collection through
* `iteratee`. The `iteratee` is bound to `thisArg` and invoked with three
* arguments; (value, index|key, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias collect
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new mapped array.
* @example
*
* _.map([1, 2, 3], function(n) { return n * 3; });
* // => [3, 6, 9]
*
* _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(n) { return n * 3; });
* // => [3, 6, 9] (iteration order is not guaranteed)
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* // using "_.pluck" callback shorthand
* _.map(users, 'user');
* // => ['barney', 'fred']
*/
function map(collection, iteratee, thisArg) {
iteratee = baseCallback(iteratee, thisArg, 3);
var func = isArray(collection) ? arrayMap : baseMap;
return func(collection, iteratee);
}
/**
* Retrieves the maximum value of `collection`. If the collection is empty
* or falsey `-Infinity` is returned. If an iteratee function is provided it
* is invoked for each value in the collection to generate the criterion by
* which the value is ranked. The `iteratee` is bound to `thisArg` and invoked
* with three arguments; (value, index, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.pluck"
* or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the maximum value.
* @example
*
* _.max([4, 2, 8, 6]);
* // => 8
*
* _.max([]);
* // => -Infinity
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.max(users, function(chr) { return chr.age; });
* // => { 'user': 'fred', 'age': 40 };
*
* // using "_.pluck" callback shorthand
* _.max(users, 'age');
* // => { 'user': 'fred', 'age': 40 };
*/
function max(collection, iteratee, thisArg) {
iteratee = isIterateeCall(collection, iteratee, thisArg) ? null : iteratee;
var computed = -Infinity,
result = computed;
if (iteratee == null) {
var index = -1,
iterable = toIterable(collection),
length = iterable.length;
while (++index < length) {
var value = iterable[index];
if (value > result) {
result = value;
}
}
} else {
iteratee = baseCallback(iteratee, thisArg, 3);
baseEach(collection, function(value, index, collection) {
var current = iteratee(value, index, collection);
if (current > computed || (current === -Infinity && current === result)) {
computed = current;
result = value;
}
});
}
return result;
}
/**
* Retrieves the minimum value of `collection`. If the collection is empty
* or falsey `Infinity` is returned. If an iteratee function is provided it
* is invoked for each value in the collection to generate the criterion by
* which the value is ranked. The `iteratee` is bound to `thisArg` and invoked
* with three arguments; (value, index, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.pluck"
* or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the minimum value.
* @example
*
* _.min([4, 2, 8, 6]);
* // => 2
*
* _.min([]);
* // => Infinity
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.min(users, function(chr) { return chr.age; });
* // => { 'user': 'barney', 'age': 36 };
*
* // using "_.pluck" callback shorthand
* _.min(users, 'age');
* // => { 'user': 'barney', 'age': 36 };
*/
function min(collection, iteratee, thisArg) {
iteratee = isIterateeCall(collection, iteratee, thisArg) ? null : iteratee;
var computed = Infinity,
result = computed;
if (iteratee == null) {
var index = -1,
iterable = toIterable(collection),
length = iterable.length;
while (++index < length) {
var value = iterable[index];
if (value < result) {
result = value;
}
}
} else {
iteratee = baseCallback(iteratee, thisArg, 3);
baseEach(collection, function(value, index, collection) {
var current = iteratee(value, index, collection);
if (current < computed || (current === Infinity && current === result)) {
computed = current;
result = value;
}
});
}
return result;
}
/**
* Creates an array of elements split into two groups, the first of which
* contains elements `predicate` returns truthy for, while the second of which
* contains elements `predicate` returns falsey for. The predicate is bound
* to `thisArg` and invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the array of grouped elements.
* @example
*
* _.partition([1, 2, 3], function(n) { return n % 2; });
* // => [[1, 3], [2]]
*
* _.partition([1.2, 2.3, 3.4], function(n) { return this.floor(n) % 2; }, Math);
* // => [[1, 3], [2]]
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true },
* { 'user': 'pebbles', 'age': 1 }
* ];
*
* // using "_.where" callback shorthand
* _.map(_.partition(users, { 'age': 1 }), function(array) { return _.pluck(array, 'user'); });
* // => [['pebbles'], ['barney', 'fred']]
*
* // using "_.pluck" callback shorthand
* _.map(_.partition(users, 'blocked'), function(array) { return _.pluck(array, 'user'); });
* // => [['fred'], ['barney', 'pebbles']]
*/
var partition = createAggregator(function(result, value, key) {
result[key ? 0 : 1].push(value);
}, function() { return [[], []]; });
/**
* Retrieves the value of a specified property from all elements in the collection.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {string} key The name of the property to pluck.
* @returns {Array} Returns the property values.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.pluck(users, 'user');
* // => ['barney', 'fred']
*
* var userIndex = _.indexBy(users, 'user');
* _.pluck(userIndex, 'age');
* // => [36, 40] (iteration order is not guaranteed)
*/
function pluck(collection, key) {
return map(collection, property(key));
}
/**
* Reduces a collection to a value which is the accumulated result of running
* each element in the collection through `iteratee`, where each successive
* invocation is supplied the return value of the previous. If `accumulator`
* is not provided the first element of the collection is used as the initial
* value. The `iteratee` is bound to `thisArg`and invoked with four arguments;
* (accumulator, value, index|key, collection).
*
* @static
* @memberOf _
* @alias foldl, inject
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=identity] The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the accumulated value.
* @example
*
* var sum = _.reduce([1, 2, 3], function(sum, n) { return sum + n; });
* // => 6
*
* var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, n, key) {
* result[key] = n * 3;
* return result;
* }, {});
* // => { 'a': 3, 'b': 6, 'c': 9 } (iteration order is not guaranteed)
*/
function reduce(collection, iteratee, accumulator, thisArg) {
var func = isArray(collection) ? arrayReduce : baseReduce;
return func(collection, baseCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEach);
}
/**
* This method is like `_.reduce` except that it iterates over elements of
* `collection` from right to left.
*
* @static
* @memberOf _
* @alias foldr
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=identity] The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the accumulated value.
* @example
*
* var array = [[0, 1], [2, 3], [4, 5]];
* _.reduceRight(array, function(flattened, other) { return flattened.concat(other); }, []);
* // => [4, 5, 2, 3, 0, 1]
*/
function reduceRight(collection, iteratee, accumulator, thisArg) {
var func = isArray(collection) ? arrayReduceRight : baseReduce;
return func(collection, baseCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEachRight);
}
/**
* The opposite of `_.filter`; this method returns the elements of `collection`
* that `predicate` does **not** return truthy for.
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the new filtered array.
* @example
*
* var odds = _.reject([1, 2, 3, 4], function(n) { return n % 2 == 0; });
* // => [1, 3]
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true }
* ];
*
* // using "_.pluck" callback shorthand
* _.reject(users, 'blocked');
* // => [{ 'user': 'barney', 'age': 36 }]
*
* // using "_.where" callback shorthand
* _.reject(users, { 'age': 36 });
* // => [{ 'user': 'fred', 'age': 40, 'blocked': true }]
*/
function reject(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayFilter : baseFilter;
predicate = baseCallback(predicate, thisArg, 3);
return func(collection, function(value, index, collection) {
return !predicate(value, index, collection);
});
}
/**
* Retrieves a random element or `n` random elements from a collection.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to sample.
* @param {number} [n] The number of elements to sample.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {*} Returns the random sample(s).
* @example
*
* _.sample([1, 2, 3, 4]);
* // => 2
*
* _.sample([1, 2, 3, 4], 2);
* // => [3, 1]
*/
function sample(collection, n, guard) {
if (guard || n == null) {
collection = toIterable(collection);
var length = collection.length;
return length > 0 ? collection[baseRandom(0, length - 1)] : undefined;
}
var result = shuffle(collection);
result.length = nativeMin(n < 0 ? 0 : (+n || 0), result.length);
return result;
}
/**
* Creates an array of shuffled values, using a version of the Fisher-Yates
* shuffle. See [Wikipedia](http://en.wikipedia.org/wiki/Fisher-Yates_shuffle)
* for more details.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to shuffle.
* @returns {Array} Returns the new shuffled array.
* @example
*
* _.shuffle([1, 2, 3, 4]);
* // => [4, 1, 3, 2]
*/
function shuffle(collection) {
collection = toIterable(collection);
var index = -1,
length = collection.length,
result = Array(length);
while (++index < length) {
var rand = baseRandom(0, index);
if (index != rand) {
result[index] = result[rand];
}
result[rand] = collection[index];
}
return result;
}
/**
* Gets the size of the collection by returning `collection.length` for
* array-like values or the number of own enumerable properties for objects.
*
* @static
* @memberOf _
* @category Collection
* @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 > -1 && length <= MAX_SAFE_INTEGER)
? length
: keys(collection).length;
}
/**
* Checks if `predicate` returns truthy for **any** element of `collection`.
* The function returns as soon as it finds a passing value and does not iterate
* over the entire collection. The predicate is bound to `thisArg` and invoked
* with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an object is provided for `predicate` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @alias any
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
* @example
*
* _.some([null, 0, 'yes', false], Boolean);
* // => true
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40, 'blocked': true }
* ];
*
* // using "_.pluck" callback shorthand
* _.some(users, 'blocked');
* // => true
*
* // using "_.where" callback shorthand
* _.some(users, { 'age': 1 });
* // => false
*/
function some(collection, predicate, thisArg) {
var func = isArray(collection) ? arraySome : baseSome;
if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
predicate = baseCallback(predicate, thisArg, 3);
}
return func(collection, predicate);
}
/**
* Creates an array of elements, sorted in ascending order by the results of
* running each element in a collection through `iteratee`. This method performs
* a stable sort, that is, it preserves the original sort order of equal elements.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `iteratee` the created "_.pluck" style
* callback returns the property value of the given element.
*
* If an array of property names is provided for `iteratee` the collection
* is sorted by each property value.
*
* If an object is provided for `iteratee` the created "_.where" style callback
* returns `true` for elements that have the properties of the given object,
* else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Array|Function|Object|string} [iteratee=identity] The function
* invoked per iteration. If property name(s) or an object is provided it
* is used to create a "_.pluck" or "_.where" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new sorted array.
* @example
*
* _.sortBy([1, 2, 3], function(n) { return Math.sin(n); });
* // => [3, 1, 2]
*
* _.sortBy([1, 2, 3], function(n) { return this.sin(n); }, Math);
* // => [3, 1, 2]
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 },
* { 'user': 'barney', 'age': 26 },
* { 'user': 'fred', 'age': 30 }
* ];
*
* // using "_.pluck" callback shorthand
* _.map(_.sortBy(users, 'age'), _.values);
* // => [['barney', 26], ['fred', 30], ['barney', 36], ['fred', 40]]
*
* // sorting by multiple properties
* _.map(_.sortBy(users, ['user', 'age']), _.values);
* // = > [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
*/
function sortBy(collection, iteratee, thisArg) {
iteratee = isIterateeCall(collection, iteratee, thisArg) ? null : iteratee;
var index = -1,
length = collection ? collection.length : 0,
result = [];
if (typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER) {
result.length = length;
}
iteratee = baseCallback(iteratee, thisArg, 3);
baseEach(collection, function(value, key, collection) {
result[++index] = {
'criteria': iteratee(value, key, collection),
'index': index,
'value': value
};
});
length = result.length;
result.sort(compareAscending);
while (length--) {
result[length] = result[length].value;
}
return result;
}
/**
* Converts `collection` to an array.
*
* @static
* @memberOf _
* @category Collection
* @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) {
var length = collection ? collection.length : 0;
if (typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER) {
return baseSlice(collection);
}
return values(collection);
}
/**
* Performs a deep comparison between each element in `collection` and the
* source object, returning an array of all elements that have equivalent
* property values.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Object} source The object of property values to match.
* @returns {Array} Returns the new filtered array.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'employer': 'slate', 'pets': ['hoppy'] },
* { 'user': 'fred', 'age': 40, 'employer': 'slate', 'pets': ['baby puss', 'dino'] }
* ];
*
* _.pluck(_.where(users, { 'age': 36 }), 'user');
* // => ['barney']
*
* _.pluck(_.where(users, { 'pets': ['dino'] }), 'user');
* // => ['fred']
*
* _.pluck(_.where(users, { 'employer': 'slate' }), 'user');
* // => ['barney', 'fred']
*/
function where(collection, source) {
return filter(collection, matches(source));
}
/*------------------------------------------------------------------------*/
/**
* The opposite of `_.before`; this method creates a function that invokes
* `func` only after it is called `n` times.
*
* @static
* @memberOf _
* @category Function
* @param {number} n The number of calls before `func` is invoked.
* @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 the two async saves have completed
*/
function after(n, func) {
if (!isFunction(func)) {
if (isFunction(n)) {
var temp = n;
n = func;
func = temp;
} else {
throw new TypeError(FUNC_ERROR_TEXT);
}
}
n = nativeIsFinite(n = +n) ? n : 0;
return function() {
if (--n < 1) {
return func.apply(this, arguments);
}
};
}
/**
* Creates a function that invokes `func`, with the `this` binding and arguments
* of the created function, while it is called less than `n` times. Subsequent
* calls to the created function return the result of the last `func` invocation.
*
* @static
* @memberOf _
* @category Function
* @param {number} n The number of calls at which `func` is no longer invoked.
* @param {Function} func The function to restrict.
* @returns {Function} Returns the new restricted function.
* @example
*
* jQuery('#add').on('click', _.before(5, addContactToList));
* // => allows adding up to 4 contacts to the list
*/
function before(n, func) {
var result;
if (!isFunction(func)) {
if (isFunction(n)) {
var temp = n;
n = func;
func = temp;
} else {
throw new TypeError(FUNC_ERROR_TEXT);
}
}
return function() {
if (--n > 0) {
result = func.apply(this, arguments);
} else {
func = null;
}
return result;
};
}
/**
* Creates a function that invokes `func` with the `this` binding of `thisArg`
* and prepends any additional `bind` arguments to those provided to the bound
* function.
*
* **Note:** Unlike native `Function#bind` this method does not set the `length`
* property of bound functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to bind.
* @param {*} [thisArg] The `this` binding of `func`.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new bound function.
* @example
*
* var func = function(greeting) {
* return greeting + ' ' + this.user;
* };
*
* func = _.bind(func, { 'user': 'fred' }, 'hi');
* func();
* // => 'hi fred'
*/
function bind(func, thisArg) {
return arguments.length < 3
? createWrapper(func, BIND_FLAG, null, thisArg)
: basePartial(func, BIND_FLAG | PARTIAL_FLAG, slice(arguments, 2), [], 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 enumerable function
* properties, own and inherited, of `object` are bound.
*
* **Note:** This method does not set the `length` property of bound functions.
*
* @static
* @memberOf _
* @category Function
* @param {Object} object The object to bind and assign the bound methods to.
* @param {...(string|string[])} [methodNames] 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 element is clicked
*/
function bindAll(object) {
return baseBindAll(object,
arguments.length > 1
? baseFlatten(arguments, false, false, 1)
: functions(object)
);
}
/**
* Creates a function that delays invoking `func` until after `wait` milliseconds
* have elapsed since the last time it was invoked. The created function comes
* with a `cancel` method to cancel delayed invocations. 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 return the result of the last `func` invocation.
*
* **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
* on the trailing edge of the timeout only if the the debounced function is
* invoked more than once during the `wait` timeout.
*
* See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
* for details over the differences between `_.debounce` and `_.throttle`.
*
* @static
* @memberOf _
* @category Function
* @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 invoking on the leading
* edge of the timeout.
* @param {number} [options.maxWait] The maximum time `func` is allowed to be
* delayed before it is invoked.
* @param {boolean} [options.trailing=true] Specify invoking 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
* jQuery(window).on('resize', _.debounce(calculateLayout, 150));
*
* // invoke `sendMail` when the click event is fired, debouncing subsequent calls
* jQuery('#postbox').on('click', _.debounce(sendMail, 300, {
* 'leading': true,
* 'trailing': false
* });
*
* // ensure `batchLog` is invoked once after 1 second of debounced calls
* var source = new EventSource('/stream');
* jQuery(source).on('message', _.debounce(batchLog, 250, {
* 'maxWait': 1000
* }, false);
*
* // cancel a debounced call
* var todoChanges = _.debounce(batchLog, 1000);
* Object.observe(models.todo, todoChanges);
*
* Object.observe(models, function(changes) {
* if (_.find(changes, { 'user': 'todo', 'type': 'delete'})) {
* todoChanges.cancel();
* }
* }, ['delete']);
*
* // ...at some point `models.todo` is changed
* models.todo.completed = true;
*
* // ...before 1 second has passed `models.todo` is deleted
* // which cancels the debounced `todoChanges` call
* delete models.todo;
*/
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(FUNC_ERROR_TEXT);
}
wait = wait < 0 ? 0 : wait;
if (options === true) {
var leading = true;
trailing = false;
} else if (isObject(options)) {
leading = options.leading;
maxWait = 'maxWait' in options && nativeMax(+options.maxWait || 0, wait);
trailing = 'trailing' in options ? options.trailing : trailing;
}
function cancel() {
if (timeoutId) {
clearTimeout(timeoutId);
}
if (maxTimeoutId) {
clearTimeout(maxTimeoutId);
}
maxTimeoutId = timeoutId = trailingCall = undefined;
}
function delayed() {
var remaining = wait - (now() - stamp);
if (remaining <= 0 || remaining > wait) {
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);
}
}
function maxDelayed() {
if (timeoutId) {
clearTimeout(timeoutId);
}
maxTimeoutId = timeoutId = trailingCall = undefined;
if (trailing || (maxWait !== wait)) {
lastCalled = now();
result = func.apply(thisArg, args);
if (!timeoutId && !maxTimeoutId) {
args = thisArg = null;
}
}
}
function debounced() {
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 || remaining > maxWait;
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;
}
debounced.cancel = cancel;
return debounced;
}
/**
* Defers invoking the `func` until the current call stack has cleared. Any
* additional arguments are provided to `func` when it is invoked.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to defer.
* @param {...*} [args] The 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(FUNC_ERROR_TEXT);
}
var args = slice(arguments, 1);
return setTimeout(function() { func.apply(undefined, args); }, 1);
}
/**
* Invokes `func` after `wait` milliseconds. Any additional arguments are
* provided to `func` when it is invoked.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to delay.
* @param {number} wait The number of milliseconds to delay invocation.
* @param {...*} [args] The 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(FUNC_ERROR_TEXT);
}
var args = slice(arguments, 2);
return setTimeout(function() { func.apply(undefined, args); }, wait);
}
/**
* This method is like `_.flow` except that it creates a function that
* invokes the provided functions from right to left.
*
* @static
* @memberOf _
* @alias backflow, compose
* @category Function
* @param {...Function} [funcs] Functions to invoke.
* @returns {Function} Returns the new function.
* @example
*
* function add(x, y) {
* return x + y;
* }
*
* function square(n) {
* return n * n;
* }
*
* var addSquare = _.flowRight(square, add);
* addSquare(1, 2);
* // => 9
*/
function flowRight() {
var funcs = arguments,
fromIndex = funcs.length - 1;
if (fromIndex < 0) {
return function() {};
}
if (!arrayEvery(funcs, isFunction)) {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function() {
var index = fromIndex,
result = funcs[index].apply(this, arguments);
while (index--) {
result = funcs[index].call(this, result);
}
return result;
};
}
/**
* Creates a function that memoizes the result of `func`. If `resolver` is
* provided it determines 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
* invoked with the `this` binding of the memoized function. The result cache
* is exposed as the `cache` property on the memoized function.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to have its output memoized.
* @param {Function} [resolver] The function 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
*
* // modifying the result cache
* var upperCase = _.memoize(function(string) {
* return string.toUpperCase();
* });
*
* upperCase('fred');
* // => 'FRED'
*
* upperCase.cache.fred = 'BARNEY'
* upperCase('fred');
* // => 'BARNEY'
*/
function memoize(func, resolver) {
if (!isFunction(func) || (resolver && !isFunction(resolver))) {
throw new TypeError(FUNC_ERROR_TEXT);
}
var memoized = function() {
var key = resolver ? resolver.apply(this, arguments) : arguments[0];
if (key == '__proto__') {
return func.apply(this, arguments);
}
var cache = memoized.cache;
return hasOwnProperty.call(cache, key)
? cache[key]
: (cache[key] = func.apply(this, arguments));
};
memoized.cache = {};
return memoized;
}
/**
* Creates a function that negates the result of the predicate `func`. The
* `func` predicate is invoked with the `this` binding and arguments of the
* created function.
*
* @static
* @memberOf _
* @category Function
* @param {Function} predicate The predicate to negate.
* @returns {Function} Returns the new function.
* @example
*
* function isEven(n) {
* return n % 2 == 0;
* }
*
* _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
* // => [1, 3, 5]
*/
function negate(predicate) {
if (!isFunction(predicate)) {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function() {
return !predicate.apply(this, arguments);
};
}
/**
* Creates a function that is restricted to invoking `func` once. Repeat calls
* to the function return the value of the first call. The `func` is invoked
* with the `this` binding of the created function.
*
* @static
* @memberOf _
* @type Function
* @category Function
* @param {Function} func The function to restrict.
* @returns {Function} Returns the new restricted function.
* @example
*
* var initialize = _.once(createApplication);
* initialize();
* initialize();
* // `initialize` invokes `createApplication` once
*/
var once = partial(before, 2);
/**
* Creates a function that invokes `func` with `partial` arguments prepended
* to those provided to the new function. This method is similar to `_.bind`
* except it does **not** alter the `this` binding.
*
* **Note:** This method does not set the `length` property of partially
* applied functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to partially apply arguments to.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new partially applied function.
* @example
*
* var greet = function(greeting, name) { return greeting + ' ' + name; };
* var sayHelloTo = _.partial(greet, 'hello');
* sayHelloTo('fred');
* // => 'hello fred'
*/
function partial(func) {
var args = slice(arguments, 1),
holders = replaceHolders(args, partial.placeholder);
return basePartial(func, PARTIAL_FLAG, args, holders);
}
/**
* Creates a function that only invokes `func` at most once per every `wait`
* milliseconds. The created function comes with a `cancel` method to cancel
* delayed invocations. 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 return the result of the last
* `func` call.
*
* **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
* on the trailing edge of the timeout only if the the throttled function is
* invoked more than once during the `wait` timeout.
*
* See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
* for details over the differences between `_.throttle` and `_.debounce`.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to throttle.
* @param {number} wait The number of milliseconds to throttle invocations to.
* @param {Object} [options] The options object.
* @param {boolean} [options.leading=true] Specify invoking on the leading
* edge of the timeout.
* @param {boolean} [options.trailing=true] Specify invoking on the trailing
* edge of the timeout.
* @returns {Function} Returns the new throttled function.
* @example
*
* // avoid excessively updating the position while scrolling
* jQuery(window).on('scroll', _.throttle(updatePosition, 100));
*
* // invoke `renewToken` when the click event is fired, but not more than once every 5 minutes
* var throttled = _.throttle(renewToken, 300000, { 'trailing': false })
* jQuery('.interactive').on('click', throttled);
*
* // cancel a trailing throttled call
* jQuery(window).on('popstate', throttled.cancel);
*/
function throttle(func, wait, options) {
var leading = true,
trailing = true;
if (!isFunction(func)) {
throw new TypeError(funcErrorText);
}
if (options === false) {
leading = false;
} else if (isObject(options)) {
leading = 'leading' in options ? options.leading : leading;
trailing = 'trailing' in options ? options.trailing : trailing;
}
return debounce(func, wait, {
'leading': leading,
'maxWait': wait,
'trailing': trailing
});
}
/**
* Creates a function that provides `value` to the wrapper function as its
* first argument. Any additional arguments provided to the function are
* appended to those provided to the wrapper function. The wrapper is invoked
* with the `this` binding of the created function.
*
* @static
* @memberOf _
* @category Function
* @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, barney, & pebbles');
* // => 'fred, barney, & pebbles
'
*/
function wrap(value, wrapper) {
return basePartial(wrapper, PARTIAL_FLAG, [value], []);
}
/*------------------------------------------------------------------------*/
/**
* Creates a clone of `value`. If `isDeep` is `true` nested objects are cloned,
* otherwise they are assigned by reference. If `customizer` is provided it is
* invoked to produce the cloned values. If `customizer` returns `undefined`
* cloning is handled by the method instead. The `customizer` is bound to
* `thisArg` and invoked with two argument; (value, index|key).
*
* **Note:** This method is loosely based on the structured clone algorithm. Functions
* and DOM nodes are **not** cloned. The enumerable properties of `arguments` objects and
* objects created by constructors other than `Object` are cloned to plain `Object` objects.
* See the [HTML5 specification](http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to clone.
* @param {boolean} [isDeep=false] Specify a deep clone.
* @param {Function} [customizer] The function to customize cloning values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {*} Returns the cloned value.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* var shallow = _.clone(users);
* shallow[0] === users[0];
* // => true
*
* var deep = _.clone(users, true);
* deep[0] === users[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) ? baseSlice(value) : assign({}, value))
: value;
}
/**
* Checks if `value` is classified as an `arguments` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an `arguments` object, else `false`.
* @example
*
* (function() { return _.isArguments(arguments); })();
* // => true
*
* _.isArguments([1, 2, 3]);
* // => false
*/
function isArguments(value) {
var length = (value && typeof value == 'object') ? value.length : undefined;
return (typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER &&
toString.call(value) == argsClass) || false;
}
// fallback for environments without a `[[Class]]` for `arguments` objects
if (!isArguments(arguments)) {
isArguments = function(value) {
var length = (value && typeof value == 'object') ? value.length : undefined;
return (typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER &&
hasOwnProperty.call(value, 'callee') && !propertyIsEnumerable.call(value, 'callee')) || false;
};
}
/**
* Checks if `value` is classified as an `Array` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isArray([1, 2, 3]);
* // => true
*
* (function() { return _.isArray(arguments); })();
* // => false
*/
var isArray = nativeIsArray || function(value) {
return (value && typeof value == 'object' && typeof value.length == 'number' &&
toString.call(value) == arrayClass) || false;
};
/**
* Checks if `value` is classified as a boolean primitive or object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isBoolean(false);
* // => true
*
* _.isBoolean(null);
* // => false
*/
function isBoolean(value) {
return (value === true || value === false || value && typeof value == 'object' &&
toString.call(value) == boolClass) || false;
}
/**
* Checks if `value` is classified as a `Date` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isDate(new Date);
* // => true
*
* _.isDate('Mon April 23 2012');
* // => false
*/
function isDate(value) {
return (value && typeof value == 'object' && toString.call(value) == dateClass) || false;
}
/**
* Checks if `value` is a DOM element.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a DOM element, else `false`.
* @example
*
* _.isElement(document.body);
* // => true
*
* _.isElement('');
* // => false
*/
function isElement(value) {
return (value && value.nodeType === 1) || false;
}
/**
* Checks if a collection is empty. A value is considered empty unless it is
* an array-like value with a length greater than `0` or an object with own
* enumerable properties.
*
* @static
* @memberOf _
* @category Lang
* @param {Array|Object|string} value The value to inspect.
* @returns {boolean} Returns `true` if `value` is empty, else `false`.
* @example
*
* _.isEmpty(null);
* // => true
*
* _.isEmpty(true);
* // => true
*
* _.isEmpty(1);
* // => true
*
* _.isEmpty([1, 2, 3]);
* // => false
*
* _.isEmpty({ 'a': 1 });
* // => false
*/
function isEmpty(value) {
if (value == null) {
return true;
}
var length = value.length;
if ((typeof length == 'number' && length > -1 && length <= MAX_SAFE_INTEGER) &&
(isArray(value) || isString(value) || isArguments(value))) {
return !length;
}
return !keys(value).length;
}
/**
* Performs a deep comparison between two values to determine if they are
* equivalent. If `customizer` is provided it is invoked to compare values.
* If `customizer` returns `undefined` comparisons are handled by the method
* instead. The `customizer` is bound to `thisArg` and invoked with three
* arguments; (value, other, key).
*
* **Note:** This method supports comparing arrays, booleans, `Date` objects,
* numbers, `Object` objects, regexes, and strings. Functions and DOM nodes
* are **not** supported. Provide a customizer function to extend support
* for comparing other values.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to compare to `other`.
* @param {*} other The value to compare to `value`.
* @param {Function} [customizer] The function to customize comparing values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {boolean} Returns `true` if the values are equivalent, else `false`.
* @example
*
* var object = { 'user': 'fred' };
* var other = { 'user': 'fred' };
*
* object == other;
* // => false
*
* _.isEqual(object, other);
* // => true
*
* var words = ['hello', 'goodbye'];
* var otherWords = ['hi', 'goodbye'];
*
* _.isEqual(words, otherWords, function() {
* return _.every(arguments, _.bind(RegExp.prototype.test, /^h(?:i|ello)$/)) || undefined;
* });
* // => true
*/
function isEqual(value, other) {
return baseIsEqual(value, other);
}
/**
* Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`,
* `SyntaxError`, `TypeError`, or `URIError` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an error object, else `false`.
* @example
*
* _.isError(new Error);
* // => true
*
* _.isError(Error);
* // => false
*/
function isError(value) {
return (value && typeof value == 'object' && toString.call(value) == errorClass) || false;
}
/**
* Checks if `value` is a finite primitive number.
*
* **Note:** This method is based on ES6 `Number.isFinite`. See the
* [ES6 spec](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isfinite)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a finite number, else `false`.
* @example
*
* _.isFinite(10);
* // => true
*
* _.isFinite('10');
* // => false
*
* _.isFinite(true);
* // => false
*
* _.isFinite(Object(10));
* // => false
*
* _.isFinite(Infinity);
* // => false
*/
function isFinite(value) {
value = parseFloat(nativeIsFinite(value) && value);
return value == value;
}
/**
* Checks if `value` is classified as a `Function` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isFunction(_);
* // => true
*
* _.isFunction(/abc/);
* // => false
*/
function isFunction(value) {
// avoid a Chakra bug in IE 11
// https://github.com/jashkenas/underscore/issues/1621
return typeof value == 'function' || false;
}
// 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('')`)
*
* **Note:** See the [ES5 spec](http://es5.github.io/#x8) for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an object, else `false`.
* @example
*
* _.isObject({});
* // => true
*
* _.isObject([1, 2, 3]);
* // => true
*
* _.isObject(1);
* // => false
*/
function isObject(value) {
// avoid a V8 bug in Chrome 19-20
// https://code.google.com/p/v8/issues/detail?id=2291
var type = typeof value;
return type == 'function' || (value && type == 'object') || false;
}
/**
* Checks if `value` is `NaN`.
*
* **Note:** This method is not the same as native `isNaN` which returns `true`
* for `undefined` and other non-numeric values. See the [ES5 spec](http://es5.github.io/#x15.1.2.4)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `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 a native function.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a native function, else `false`.
* @example
*
* _.isNative(Array.prototype.push);
* // => true
*
* _.isNative(_);
* // => false
*/
function isNative(value) {
if (isFunction(value)) {
return reNative.test(fnToString.call(value));
}
return (value && typeof value == 'object' && reHostCtor.test(value)) || false;
}
/**
* Checks if `value` is `null`.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is `null`, else `false`.
* @example
*
* _.isNull(null);
* // => true
*
* _.isNull(void 0);
* // => false
*/
function isNull(value) {
return value === null;
}
/**
* Checks if `value` is classified as a `Number` primitive or object.
*
* **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are classified
* as numbers, use the `_.isFinite` method.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isNumber(8.4);
* // => true
*
* _.isNumber(NaN);
* // => true
*
* _.isNumber('8.4');
* // => false
*/
function isNumber(value) {
var type = typeof value;
return type == 'number' || (value && type == 'object' && toString.call(value) == numberClass) || false;
}
/**
* Checks if `value` is classified as a `RegExp` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isRegExp(/abc/);
* // => true
*
* _.isRegExp('/abc/');
* // => false
*/
function isRegExp(value) {
return (isObject(value) && toString.call(value) == regexpClass) || false;
}
/**
* Checks if `value` is classified as a `String` primitive or object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isString('abc');
* // => true
*
* _.isString(1);
* // => false
*/
function isString(value) {
return typeof value == 'string' || (value && typeof value == 'object' &&
toString.call(value) == stringClass) || false;
}
/**
* Checks if `value` is `undefined`.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is `undefined`, else `false`.
* @example
*
* _.isUndefined(void 0);
* // => true
*
* _.isUndefined(null);
* // => false
*/
function isUndefined(value) {
return typeof value == 'undefined';
}
/*------------------------------------------------------------------------*/
/**
* Assigns own enumerable properties of source object(s) to the destination
* object. Subsequent sources overwrite property assignments of previous sources.
* If `customizer` is provided it is invoked to produce the assigned values.
* The `customizer` is bound to `thisArg` and invoked with five arguments;
* (objectValue, sourceValue, key, object, source).
*
* @static
* @memberOf _
* @alias extend
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @param {Function} [customizer] The function to customize assigning values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {Object} Returns the destination object.
* @example
*
* _.assign({ 'user': 'fred' }, { 'age': 40 }, { 'employer': 'slate' });
* // => { 'user': 'fred', 'age': 40, 'employer': 'slate' }
*
* var defaults = _.partialRight(_.assign, function(value, other) {
* return typeof value == 'undefined' ? other : value;
* });
*
* defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred', 'employer': 'slate' });
* // => { 'user': 'barney', 'age': 36, 'employer': 'slate' }
*/
function assign(object) {
if (object == null) {
return object;
}
var args = arguments,
index = 0,
length = args.length;
if (isIterateeCall(args[1], args[2], args[3])) {
length = 2;
}
while (++index < length) {
baseAssign(object, args[index]);
}
return object;
}
/**
* 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 are ignored.
*
* **Note:** See the [documentation example of `_.partialRight`](http://lodash.com/docs#partialRight)
* for a deep version of this method.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @returns {Object} Returns the destination object.
* @example
*
* _.defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred', 'employer': 'slate' });
* // => { 'user': 'barney', 'age': 36, 'employer': 'slate' }
*/
function defaults(object) {
if (object == null) {
return object;
}
var args = arguments,
index = 0,
length = args.length;
if (isIterateeCall(args[1], args[2], args[3])) {
length = 2;
}
while (++index < length) {
var source = args[index];
for (var key in source) {
if (typeof object[key] == 'undefined') {
object[key] = source[key];
}
}
}
return object;
}
/**
* Creates an array of function property names from all enumerable properties,
* own and inherited, of `object`.
*
* @static
* @memberOf _
* @alias methods
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the new array of property names.
* @example
*
* _.functions(_);
* // => ['all', 'any', 'bind', ...]
*/
function functions(object) {
return baseFunctions(object, keysIn(object));
}
/**
* Checks if the specified property name exists as a direct property of `object`,
* instead of an inherited property.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @param {string} key The name of the property to check.
* @returns {boolean} Returns `true` if key is a direct property, else `false`.
* @example
*
* _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b');
* // => true
*/
function has(object, key) {
return object ? hasOwnProperty.call(object, key) : false;
}
/**
* Creates an object composed of the inverted keys and values of the given
* object. If the given object contains duplicate values, subsequent values
* overwrite property assignments of previous values unless `multiValue`
* is `true`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to invert.
* @param {boolean} [multiValue=false] Allow multiple values per key.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Object} Returns the new inverted object.
* @example
*
* _.invert({ 'first': 'fred', 'second': 'barney' });
* // => { 'fred': 'first', 'barney': 'second' }
*
* // without `multiValue`
* _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' });
* // => { 'fred': 'third', 'barney': 'second' }
*
* // with `multiValue`
* _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' }, true);
* // => { 'fred': ['first', 'third'], 'barney': ['second'] }
*/
function invert(object) {
var index = -1,
props = keys(object),
length = props.length,
result = {};
while (++index < length) {
var key = props[index];
result[object[key]] = key;
}
return result;
}
/**
* Creates an array of the own enumerable property names of `object`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
* @example
*
* function Shape() {
* this.x = 0;
* this.y = 0;
* }
*
* Shape.prototype.z = 0;
*
* _.keys(new Shape);
* // => ['x', 'y'] (iteration order is not guaranteed)
*/
var keys = !nativeKeys ? shimKeys : function(object) {
return isObject(object) ? nativeKeys(object) : [];
};
/**
* Creates an array of the own and inherited enumerable property names of `object`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
* @example
*
* function Shape() {
* this.x = 0;
* this.y = 0;
* }
*
* Shape.prototype.z = 0;
*
* _.keysIn(new Shape);
* // => ['x', 'y', 'z'] (iteration order is not guaranteed)
*/
function keysIn(object) {
var result = [];
if (!isObject(object)) {
return result;
}
for (var key in object) {
result.push(key);
}
return result;
}
/**
* 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 `predicate` is provided it is invoked for each property
* of `object` omitting the properties `predicate` returns truthy for. The
* predicate is bound to `thisArg` and invoked with three arguments;
* (value, key, object).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The source object.
* @param {Function|...(string|string[])} [predicate] The function invoked per
* iteration or property names to omit, specified as individual property
* names or arrays of property names.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Object} Returns the new object.
* @example
*
* _.omit({ 'user': 'fred', 'age': 40 }, 'age');
* // => { 'user': 'fred' }
*
* _.omit({ 'user': 'fred', 'age': 40 }, function(value) {
* return typeof value == 'number';
* });
* // => { 'user': 'fred' }
*/
function omit(object, predicate, thisArg) {
if (object == null) {
return {};
}
if (typeof predicate != 'function') {
var props = arrayMap(baseFlatten(arguments, false, false, 1), String);
return pickByArray(object, baseDifference(keysIn(object), props));
}
predicate = baseCallback(predicate, thisArg, 3);
return pickByCallback(object, function(value, key, object) {
return !predicate(value, key, object);
});
}
/**
* Creates a two dimensional array of a given object's key-value pairs,
* e.g. `[[key1, value1], [key2, value2]]`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the new array of key-value pairs.
* @example
*
* _.pairs({ 'barney': 36, 'fred': 40 });
* // => [['barney', 36], ['fred', 40]] (iteration order is not guaranteed)
*/
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 `predicate` is provided it is invoked for each property
* of `object` picking the properties `predicate` returns truthy for. The
* predicate is bound to `thisArg` and invoked with three arguments;
* (value, key, object).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The source object.
* @param {Function|...(string|string[])} [predicate] The function invoked per
* iteration or property names to pick, specified as individual property
* names or arrays of property names.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Object} Returns the new object.
* @example
*
* _.pick({ 'user': 'fred', '_userid': 'fred1' }, 'user');
* // => { 'user': 'fred' }
*
* _.pick({ 'user': 'fred', '_userid': 'fred1' }, function(value, key) {
* return key.charAt(0) != '_';
* });
* // => { 'user': 'fred' }
*/
function pick(object, predicate, thisArg) {
if (object == null) {
return {};
}
return typeof predicate == 'function'
? pickByCallback(object, baseCallback(predicate, thisArg, 3))
: pickByArray(object, baseFlatten(arguments, false, false, 1));
}
/**
* Creates an array of the own enumerable property values of `object`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property values.
* @example
*
* function Shape(x, y) {
* this.x = x;
* this.y = y;
* }
*
* Shape.prototype.z = 0;
*
* _.values(new Shape(2, 1));
* // => [2, 1] (iteration order is not guaranteed)
*/
function values(object) {
return baseValues(object, keys);
}
/*------------------------------------------------------------------------*/
/**
* Converts the characters "&", "<", ">", '"', "'", and '`', in `string` to
* their corresponding HTML entities.
*
* **Note:** No other characters are escaped. To escape additional characters
* use a third-party library like [_he_](http://mths.be/he).
*
* When working with HTML you should always quote attribute values to reduce
* XSS vectors. See [Ryan Grove's article](http://wonko.com/post/html-escaping)
* for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to escape.
* @returns {string} Returns the escaped string.
* @example
*
* _.escape('fred, barney, & pebbles');
* // => 'fred, barney, & pebbles'
*/
function escape(string) {
// reset `lastIndex` because in IE < 9 `String#replace` does not
string = string == null ? '' : String(string);
return string && (reUnescapedHtml.lastIndex = 0, reUnescapedHtml.test(string))
? string.replace(reUnescapedHtml, escapeHtmlChar)
: string;
}
/**
* Escapes the `RegExp` special characters "\", "^", "$", ".", "|", "?", "*",
* "+", "(", ")", "[", "]", "{" and "}" in `string`.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to escape.
* @returns {string} Returns the escaped string.
* @example
*
* _.escapeRegExp('[lodash](http://lodash.com/)');
* // => '\[lodash\]\(http://lodash\.com/\)'
*/
function escapeRegExp(string) {
string = string == null ? '' : String(string);
return string && (reRegExpChars.lastIndex = 0, reRegExpChars.test(string))
? string.replace(reRegExpChars, '\\$&')
: string;
}
/**
* Creates a compiled template function that can interpolate data properties
* in "interpolate" delimiters, HTML-escape interpolated data properties in
* "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
* properties may be accessed as free variables in the template. If a setting
* object is provided it overrides `_.templateSettings` for the template.
*
* **Note:** In the development build `_.template` utilizes sourceURLs for easier debugging.
* See the [HTML5 Rocks article on sourcemaps](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)
* for more details.
*
* For more information on precompiling templates see
* [Lo-Dash's custom builds documentation](http://lodash.com/custom-builds).
*
* For more information on Chrome extension sandboxes see
* [Chrome's extensions documentation](http://developer.chrome.com/stable/extensions/sandboxingEval.html).
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The template string.
* @param {Object} [options] The options object.
* @param {RegExp} [options.escape] The HTML "escape" delimiter.
* @param {RegExp} [options.evaluate] The "evaluate" delimiter.
* @param {Object} [options.imports] An object to import into the template as free variables.
* @param {RegExp} [options.interpolate] The "interpolate" delimiter.
* @param {string} [options.sourceURL] The sourceURL of the template's compiled source.
* @param {string} [options.variable] The data object variable name.
* @param- {Object} [otherOptions] Enables the legacy `options` param signature.
* @returns {Function} Returns the compiled template function.
* @example
*
* // using the "interpolate" delimiter to create a compiled template
* var compiled = _.template('hello <%= user %>!');
* compiled({ 'user': 'fred' });
* // => 'hello fred!'
*
* // using the HTML "escape" delimiter to escape data property values
* var compiled = _.template('<%- value %>');
* compiled({ 'value': '