diff options
Diffstat (limited to 'node_modules/lodash/core.js')
| -rw-r--r-- | node_modules/lodash/core.js | 3854 |
1 files changed, 3854 insertions, 0 deletions
diff --git a/node_modules/lodash/core.js b/node_modules/lodash/core.js new file mode 100644 index 0000000..f313474 --- /dev/null +++ b/node_modules/lodash/core.js @@ -0,0 +1,3854 @@ +/** + * @license + * Lodash (Custom Build) <https://lodash.com/> + * Build: `lodash core -o ./dist/lodash.core.js` + * Copyright OpenJS Foundation and other contributors <https://openjsf.org/> + * Released under MIT license <https://lodash.com/license> + * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE> + * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors + */ +;(function() { + + /** Used as a safe reference for `undefined` in pre-ES5 environments. */ + var undefined; + + /** Used as the semantic version number. */ + var VERSION = '4.17.14'; + + /** Error message constants. */ + var FUNC_ERROR_TEXT = 'Expected a function'; + + /** Used to compose bitmasks for value comparisons. */ + var COMPARE_PARTIAL_FLAG = 1, + COMPARE_UNORDERED_FLAG = 2; + + /** Used to compose bitmasks for function metadata. */ + var WRAP_BIND_FLAG = 1, + WRAP_PARTIAL_FLAG = 32; + + /** Used as references for various `Number` constants. */ + var INFINITY = 1 / 0, + MAX_SAFE_INTEGER = 9007199254740991; + + /** `Object#toString` result references. */ + var argsTag = '[object Arguments]', + arrayTag = '[object Array]', + asyncTag = '[object AsyncFunction]', + boolTag = '[object Boolean]', + dateTag = '[object Date]', + errorTag = '[object Error]', + funcTag = '[object Function]', + genTag = '[object GeneratorFunction]', + numberTag = '[object Number]', + objectTag = '[object Object]', + proxyTag = '[object Proxy]', + regexpTag = '[object RegExp]', + stringTag = '[object String]'; + + /** Used to match HTML entities and HTML characters. */ + var reUnescapedHtml = /[&<>"']/g, + reHasUnescapedHtml = RegExp(reUnescapedHtml.source); + + /** Used to detect unsigned integer values. */ + var reIsUint = /^(?:0|[1-9]\d*)$/; + + /** Used to map characters to HTML entities. */ + var htmlEscapes = { + '&': '&', + '<': '<', + '>': '>', + '"': '"', + "'": ''' + }; + + /** Detect free variable `global` from Node.js. */ + var freeGlobal = typeof global == 'object' && global && global.Object === Object && global; + + /** Detect free variable `self`. */ + var freeSelf = typeof self == 'object' && self && self.Object === Object && self; + + /** Used as a reference to the global object. */ + var root = freeGlobal || freeSelf || Function('return this')(); + + /** Detect free variable `exports`. */ + var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports; + + /** Detect free variable `module`. */ + var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module; + + /*--------------------------------------------------------------------------*/ + + /** + * Appends the elements of `values` to `array`. + * + * @private + * @param {Array} array The array to modify. + * @param {Array} values The values to append. + * @returns {Array} Returns `array`. + */ + function arrayPush(array, values) { + array.push.apply(array, values); + return array; + } + + /** + * The base implementation of `_.findIndex` and `_.findLastIndex` without + * support for iteratee shorthands. + * + * @private + * @param {Array} array The array to inspect. + * @param {Function} predicate The function invoked per iteration. + * @param {number} fromIndex The index to search from. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {number} Returns the index of the matched value, else `-1`. + */ + function baseFindIndex(array, predicate, fromIndex, fromRight) { + var length = array.length, + index = fromIndex + (fromRight ? 1 : -1); + + while ((fromRight ? index-- : ++index < length)) { + if (predicate(array[index], index, array)) { + return index; + } + } + return -1; + } + + /** + * The base implementation of `_.property` without support for deep paths. + * + * @private + * @param {string} key The key of the property to get. + * @returns {Function} Returns the new accessor function. + */ + function baseProperty(key) { + return function(object) { + return object == null ? undefined : object[key]; + }; + } + + /** + * The base implementation of `_.propertyOf` without support for deep paths. + * + * @private + * @param {Object} object The object to query. + * @returns {Function} Returns the new accessor function. + */ + function basePropertyOf(object) { + return function(key) { + return object == null ? undefined : object[key]; + }; + } + + /** + * The base implementation of `_.reduce` and `_.reduceRight`, without support + * for iteratee shorthands, which iterates over `collection` using `eachFunc`. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @param {*} accumulator The initial value. + * @param {boolean} initAccum 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, initAccum, eachFunc) { + eachFunc(collection, function(value, index, collection) { + accumulator = initAccum + ? (initAccum = false, value) + : iteratee(accumulator, value, index, collection); + }); + return accumulator; + } + + /** + * The base implementation of `_.values` and `_.valuesIn` which creates an + * array of `object` property values corresponding to the property names + * of `props`. + * + * @private + * @param {Object} object The object to query. + * @param {Array} props The property names to get values for. + * @returns {Object} Returns the array of property values. + */ + function baseValues(object, props) { + return baseMap(props, function(key) { + return object[key]; + }); + } + + /** + * Used by `_.escape` to convert characters to HTML entities. + * + * @private + * @param {string} chr The matched character to escape. + * @returns {string} Returns the escaped character. + */ + var escapeHtmlChar = basePropertyOf(htmlEscapes); + + /** + * Creates a unary function that invokes `func` with its argument transformed. + * + * @private + * @param {Function} func The function to wrap. + * @param {Function} transform The argument transform. + * @returns {Function} Returns the new function. + */ + function overArg(func, transform) { + return function(arg) { + return func(transform(arg)); + }; + } + + /*--------------------------------------------------------------------------*/ + + /** Used for built-in method references. */ + var arrayProto = Array.prototype, + objectProto = Object.prototype; + + /** Used to check objects for own properties. */ + var hasOwnProperty = objectProto.hasOwnProperty; + + /** Used to generate unique IDs. */ + var idCounter = 0; + + /** + * Used to resolve the + * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring) + * of values. + */ + var nativeObjectToString = objectProto.toString; + + /** Used to restore the original `_` reference in `_.noConflict`. */ + var oldDash = root._; + + /** Built-in value references. */ + var objectCreate = Object.create, + propertyIsEnumerable = objectProto.propertyIsEnumerable; + + /* Built-in method references for those with the same name as other `lodash` methods. */ + var nativeIsFinite = root.isFinite, + nativeKeys = overArg(Object.keys, Object), + nativeMax = Math.max; + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` object which wraps `value` to enable implicit method + * chain sequences. Methods that operate on and return arrays, collections, + * and functions can be chained together. Methods that retrieve a single value + * or may return a primitive value will automatically end the chain sequence + * and return the unwrapped value. Otherwise, the value must be unwrapped + * with `_#value`. + * + * Explicit chain sequences, which must be unwrapped with `_#value`, may be + * enabled using `_.chain`. + * + * The execution of chained methods is lazy, that is, it's deferred until + * `_#value` is implicitly or explicitly called. + * + * Lazy evaluation allows several methods to support shortcut fusion. + * Shortcut fusion is an optimization to merge iteratee calls; this avoids + * the creation of intermediate arrays and can greatly reduce the number of + * iteratee executions. Sections of a chain sequence qualify for shortcut + * fusion if the section is applied to an array and iteratees accept only + * one argument. The heuristic for whether a section qualifies for shortcut + * fusion is subject to change. + * + * Chaining is supported in custom builds as long as the `_#value` method is + * directly or indirectly included in the build. + * + * In addition to lodash methods, wrappers have `Array` and `String` methods. + * + * The wrapper `Array` methods are: + * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift` + * + * The wrapper `String` methods are: + * `replace` and `split` + * + * The wrapper methods that support shortcut fusion are: + * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`, + * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`, + * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray` + * + * The chainable wrapper methods are: + * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`, + * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`, + * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`, + * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`, + * `difference`, `differenceBy`, `differenceWith`, `drop`, `dropRight`, + * `dropRightWhile`, `dropWhile`, `extend`, `extendWith`, `fill`, `filter`, + * `flatMap`, `flatMapDeep`, `flatMapDepth`, `flatten`, `flattenDeep`, + * `flattenDepth`, `flip`, `flow`, `flowRight`, `fromPairs`, `functions`, + * `functionsIn`, `groupBy`, `initial`, `intersection`, `intersectionBy`, + * `intersectionWith`, `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`, + * `keys`, `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`, + * `memoize`, `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`, + * `nthArg`, `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`, + * `overEvery`, `overSome`, `partial`, `partialRight`, `partition`, `pick`, + * `pickBy`, `plant`, `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`, + * `pullAllWith`, `pullAt`, `push`, `range`, `rangeRight`, `rearg`, `reject`, + * `remove`, `rest`, `reverse`, `sampleSize`, `set`, `setWith`, `shuffle`, + * `slice`, `sort`, `sortBy`, `splice`, `spread`, `tail`, `take`, `takeRight`, + * `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `toArray`, + * `toPairs`, `toPairsIn`, `toPath`, `toPlainObject`, `transform`, `unary`, + * `union`, `unionBy`, `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`, + * `unshift`, `unzip`, `unzipWith`, `update`, `updateWith`, `values`, + * `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, `xorWith`, `zip`, + * `zipObject`, `zipObjectDeep`, and `zipWith` + * + * The wrapper methods that are **not** chainable by default are: + * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`, + * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `conformsTo`, `deburr`, + * `defaultTo`, `divide`, `each`, `eachRight`, `endsWith`, `eq`, `escape`, + * `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`, + * `findLastIndex`, `findLastKey`, `first`, `floor`, `forEach`, `forEachRight`, + * `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`, + * `hasIn`, `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`, + * `isArguments`, `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`, + * `isBoolean`, `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`, + * `isEqualWith`, `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`, + * `isMap`, `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`, + * `isNumber`, `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`, + * `isSafeInteger`, `isSet`, `isString`, `isUndefined`, `isTypedArray`, + * `isWeakMap`, `isWeakSet`, `join`, `kebabCase`, `last`, `lastIndexOf`, + * `lowerCase`, `lowerFirst`, `lt`, `lte`, `max`, `maxBy`, `mean`, `meanBy`, + * `min`, `minBy`, `multiply`, `noConflict`, `noop`, `now`, `nth`, `pad`, + * `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`, + * `repeat`, `result`, `round`, `runInContext`, `sample`, `shift`, `size`, + * `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, `sortedLastIndex`, + * `sortedLastIndexBy`, `startCase`, `startsWith`, `stubArray`, `stubFalse`, + * `stubObject`, `stubString`, `stubTrue`, `subtract`, `sum`, `sumBy`, + * `template`, `times`, `toFinite`, `toInteger`, `toJSON`, `toLength`, + * `toLower`, `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`, + * `trimEnd`, `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`, + * `upperFirst`, `value`, and `words` + * + * @name _ + * @constructor + * @category Seq + * @param {*} value The value to wrap in a `lodash` instance. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * function square(n) { + * return n * n; + * } + * + * var wrapped = _([1, 2, 3]); + * + * // Returns an unwrapped value. + * wrapped.reduce(_.add); + * // => 6 + * + * // Returns a wrapped value. + * var squares = wrapped.map(square); + * + * _.isArray(squares); + * // => false + * + * _.isArray(squares.value()); + * // => true + */ + function lodash(value) { + return value instanceof LodashWrapper + ? value + : new LodashWrapper(value); + } + + /** + * The base implementation of `_.create` without support for assigning + * properties to the created object. + * + * @private + * @param {Object} proto The object to inherit from. + * @returns {Object} Returns the new object. + */ + var baseCreate = (function() { + function object() {} + return function(proto) { + if (!isObject(proto)) { + return {}; + } + if (objectCreate) { + return objectCreate(proto); + } + object.prototype = proto; + var result = new object; + object.prototype = undefined; + return result; + }; + }()); + + /** + * The base constructor for creating `lodash` wrapper objects. + * + * @private + * @param {*} value The value to wrap. + * @param {boolean} [chainAll] Enable explicit method chain sequences. + */ + function LodashWrapper(value, chainAll) { + this.__wrapped__ = value; + this.__actions__ = []; + this.__chain__ = !!chainAll; + } + + LodashWrapper.prototype = baseCreate(lodash.prototype); + LodashWrapper.prototype.constructor = LodashWrapper; + + /*------------------------------------------------------------------------*/ + + /** + * Assigns `value` to `key` of `object` if the existing value is not equivalent + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function assignValue(object, key, value) { + var objValue = object[key]; + if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) || + (value === undefined && !(key in object))) { + baseAssignValue(object, key, value); + } + } + + /** + * The base implementation of `assignValue` and `assignMergeValue` without + * value checks. + * + * @private + * @param {Object} object The object to modify. + * @param {string} key The key of the property to assign. + * @param {*} value The value to assign. + */ + function baseAssignValue(object, key, value) { + object[key] = value; + } + + /** + * The base implementation of `_.delay` and `_.defer` which accepts `args` + * to provide to `func`. + * + * @private + * @param {Function} func The function to delay. + * @param {number} wait The number of milliseconds to delay invocation. + * @param {Array} args The arguments to provide to `func`. + * @returns {number|Object} Returns the timer id or timeout object. + */ + function baseDelay(func, wait, args) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return setTimeout(function() { func.apply(undefined, args); }, wait); + } + + /** + * The base implementation of `_.forEach` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} iteratee The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + */ + var baseEach = createBaseEach(baseForOwn); + + /** + * The base implementation of `_.every` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} predicate The function invoked per iteration. + * @returns {boolean} 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; + }); + return result; + } + + /** + * The base implementation of methods like `_.max` and `_.min` which accepts a + * `comparator` to determine the extremum value. + * + * @private + * @param {Array} array The array to iterate over. + * @param {Function} iteratee The iteratee invoked per iteration. + * @param {Function} comparator The comparator used to compare values. + * @returns {*} Returns the extremum value. + */ + function baseExtremum(array, iteratee, comparator) { + var index = -1, + length = array.length; + + while (++index < length) { + var value = array[index], + current = iteratee(value); + + if (current != null && (computed === undefined + ? (current === current && !false) + : comparator(current, computed) + )) { + var computed = current, + result = value; + } + } + return result; + } + + /** + * The base implementation of `_.filter` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} 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 `_.flatten` with support for restricting flattening. + * + * @private + * @param {Array} array The array to flatten. + * @param {number} depth The maximum recursion depth. + * @param {boolean} [predicate=isFlattenable] The function invoked per iteration. + * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks. + * @param {Array} [result=[]] The initial result value. + * @returns {Array} Returns the new flattened array. + */ + function baseFlatten(array, depth, predicate, isStrict, result) { + var index = -1, + length = array.length; + + predicate || (predicate = isFlattenable); + result || (result = []); + + while (++index < length) { + var value = array[index]; + if (depth > 0 && predicate(value)) { + if (depth > 1) { + // Recursively flatten arrays (susceptible to call stack limits). + baseFlatten(value, depth - 1, predicate, isStrict, result); + } else { + arrayPush(result, value); + } + } else if (!isStrict) { + result[result.length] = value; + } + } + return result; + } + + /** + * The base implementation of `baseForOwn` which iterates over `object` + * properties returned by `keysFunc` and invokes `iteratee` for each property. + * Iteratee 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`. + */ + var baseFor = createBaseFor(); + + /** + * The base implementation of `_.forOwn` without support for iteratee shorthands. + * + * @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 object && baseFor(object, iteratee, keys); + } + + /** + * The base implementation of `_.functions` which creates an array of + * `object` function property names filtered from `props`. + * + * @private + * @param {Object} object The object to inspect. + * @param {Array} props The property names to filter. + * @returns {Array} Returns the function names. + */ + function baseFunctions(object, props) { + return baseFilter(props, function(key) { + return isFunction(object[key]); + }); + } + + /** + * The base implementation of `getTag` without fallbacks for buggy environments. + * + * @private + * @param {*} value The value to query. + * @returns {string} Returns the `toStringTag`. + */ + function baseGetTag(value) { + return objectToString(value); + } + + /** + * The base implementation of `_.gt` which doesn't coerce arguments. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is greater than `other`, + * else `false`. + */ + function baseGt(value, other) { + return value > other; + } + + /** + * The base implementation of `_.isArguments`. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an `arguments` object, + */ + var baseIsArguments = noop; + + /** + * The base implementation of `_.isDate` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a date object, else `false`. + */ + function baseIsDate(value) { + return isObjectLike(value) && baseGetTag(value) == dateTag; + } + + /** + * The base implementation of `_.isEqual` which supports partial comparisons + * and tracks traversed objects. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @param {boolean} bitmask The bitmask flags. + * 1 - Unordered comparison + * 2 - Partial comparison + * @param {Function} [customizer] The function to customize comparisons. + * @param {Object} [stack] Tracks traversed `value` and `other` objects. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + */ + function baseIsEqual(value, other, bitmask, customizer, stack) { + if (value === other) { + return true; + } + if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) { + return value !== value && other !== other; + } + return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack); + } + + /** + * A specialized version of `baseIsEqual` for arrays and objects which performs + * deep comparisons and tracks traversed objects enabling objects with circular + * references to be compared. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} [stack] Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) { + var objIsArr = isArray(object), + othIsArr = isArray(other), + objTag = objIsArr ? arrayTag : baseGetTag(object), + othTag = othIsArr ? arrayTag : baseGetTag(other); + + objTag = objTag == argsTag ? objectTag : objTag; + othTag = othTag == argsTag ? objectTag : othTag; + + var objIsObj = objTag == objectTag, + othIsObj = othTag == objectTag, + isSameTag = objTag == othTag; + + stack || (stack = []); + var objStack = find(stack, function(entry) { + return entry[0] == object; + }); + var othStack = find(stack, function(entry) { + return entry[0] == other; + }); + if (objStack && othStack) { + return objStack[1] == other; + } + stack.push([object, other]); + stack.push([other, object]); + if (isSameTag && !objIsObj) { + var result = (objIsArr) + ? equalArrays(object, other, bitmask, customizer, equalFunc, stack) + : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack); + stack.pop(); + return result; + } + if (!(bitmask & COMPARE_PARTIAL_FLAG)) { + var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'), + othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__'); + + if (objIsWrapped || othIsWrapped) { + var objUnwrapped = objIsWrapped ? object.value() : object, + othUnwrapped = othIsWrapped ? other.value() : other; + + var result = equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack); + stack.pop(); + return result; + } + } + if (!isSameTag) { + return false; + } + var result = equalObjects(object, other, bitmask, customizer, equalFunc, stack); + stack.pop(); + return result; + } + + /** + * The base implementation of `_.isRegExp` without Node.js optimizations. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a regexp, else `false`. + */ + function baseIsRegExp(value) { + return isObjectLike(value) && baseGetTag(value) == regexpTag; + } + + /** + * The base implementation of `_.iteratee`. + * + * @private + * @param {*} [value=_.identity] The value to convert to an iteratee. + * @returns {Function} Returns the iteratee. + */ + function baseIteratee(func) { + if (typeof func == 'function') { + return func; + } + if (func == null) { + return identity; + } + return (typeof func == 'object' ? baseMatches : baseProperty)(func); + } + + /** + * The base implementation of `_.lt` which doesn't coerce arguments. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if `value` is less than `other`, + * else `false`. + */ + function baseLt(value, other) { + return value < other; + } + + /** + * The base implementation of `_.map` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} 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 index = -1, + result = isArrayLike(collection) ? Array(collection.length) : []; + + baseEach(collection, function(value, key, collection) { + result[++index] = iteratee(value, key, collection); + }); + return result; + } + + /** + * The base implementation of `_.matches` which doesn't clone `source`. + * + * @private + * @param {Object} source The object of property values to match. + * @returns {Function} Returns the new spec function. + */ + function baseMatches(source) { + var props = nativeKeys(source); + return function(object) { + var length = props.length; + if (object == null) { + return !length; + } + object = Object(object); + while (length--) { + var key = props[length]; + if (!(key in object && + baseIsEqual(source[key], object[key], COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG) + )) { + return false; + } + } + return true; + }; + } + + /** + * The base implementation of `_.pick` without support for individual + * property identifiers. + * + * @private + * @param {Object} object The source object. + * @param {string[]} paths The property paths to pick. + * @returns {Object} Returns the new object. + */ + function basePick(object, props) { + object = Object(object); + return reduce(props, function(result, key) { + if (key in object) { + result[key] = object[key]; + } + return result; + }, {}); + } + + /** + * The base implementation of `_.rest` which doesn't validate or coerce arguments. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @returns {Function} Returns the new function. + */ + function baseRest(func, start) { + return setToString(overRest(func, start, identity), func + ''); + } + + /** + * The base implementation of `_.slice` without an iteratee call guard. + * + * @private + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function baseSlice(array, start, end) { + var index = -1, + length = array.length; + + if (start < 0) { + start = -start > length ? 0 : (length + start); + } + end = end > length ? length : end; + if (end < 0) { + end += length; + } + length = start > end ? 0 : ((end - start) >>> 0); + start >>>= 0; + + var result = Array(length); + while (++index < length) { + result[index] = array[index + start]; + } + return result; + } + + /** + * Copies the values of `source` to `array`. + * + * @private + * @param {Array} source The array to copy values from. + * @param {Array} [array=[]] The array to copy values to. + * @returns {Array} Returns `array`. + */ + function copyArray(source) { + return baseSlice(source, 0, source.length); + } + + /** + * The base implementation of `_.some` without support for iteratee shorthands. + * + * @private + * @param {Array|Object} 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; + }); + return !!result; + } + + /** + * The base implementation of `wrapperValue` which returns the result of + * performing a sequence of actions on the unwrapped `value`, where each + * successive action is supplied the return value of the previous. + * + * @private + * @param {*} value The unwrapped value. + * @param {Array} actions Actions to perform to resolve the unwrapped value. + * @returns {*} Returns the resolved value. + */ + function baseWrapperValue(value, actions) { + var result = value; + return reduce(actions, function(result, action) { + return action.func.apply(action.thisArg, arrayPush([result], action.args)); + }, result); + } + + /** + * Compares values to sort them in ascending order. + * + * @private + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {number} Returns the sort order indicator for `value`. + */ + function compareAscending(value, other) { + if (value !== other) { + var valIsDefined = value !== undefined, + valIsNull = value === null, + valIsReflexive = value === value, + valIsSymbol = false; + + var othIsDefined = other !== undefined, + othIsNull = other === null, + othIsReflexive = other === other, + othIsSymbol = false; + + if ((!othIsNull && !othIsSymbol && !valIsSymbol && value > other) || + (valIsSymbol && othIsDefined && othIsReflexive && !othIsNull && !othIsSymbol) || + (valIsNull && othIsDefined && othIsReflexive) || + (!valIsDefined && othIsReflexive) || + !valIsReflexive) { + return 1; + } + if ((!valIsNull && !valIsSymbol && !othIsSymbol && value < other) || + (othIsSymbol && valIsDefined && valIsReflexive && !valIsNull && !valIsSymbol) || + (othIsNull && valIsDefined && valIsReflexive) || + (!othIsDefined && valIsReflexive) || + !othIsReflexive) { + return -1; + } + } + return 0; + } + + /** + * Copies properties of `source` to `object`. + * + * @private + * @param {Object} source The object to copy properties from. + * @param {Array} props The property identifiers to copy. + * @param {Object} [object={}] The object to copy properties to. + * @param {Function} [customizer] The function to customize copied values. + * @returns {Object} Returns `object`. + */ + function copyObject(source, props, object, customizer) { + var isNew = !object; + object || (object = {}); + + var index = -1, + length = props.length; + + while (++index < length) { + var key = props[index]; + + var newValue = customizer + ? customizer(object[key], source[key], key, object, source) + : undefined; + + if (newValue === undefined) { + newValue = source[key]; + } + if (isNew) { + baseAssignValue(object, key, newValue); + } else { + assignValue(object, key, newValue); + } + } + return object; + } + + /** + * Creates a function like `_.assign`. + * + * @private + * @param {Function} assigner The function to assign values. + * @returns {Function} Returns the new assigner function. + */ + function createAssigner(assigner) { + return baseRest(function(object, sources) { + var index = -1, + length = sources.length, + customizer = length > 1 ? sources[length - 1] : undefined; + + customizer = (assigner.length > 3 && typeof customizer == 'function') + ? (length--, customizer) + : undefined; + + object = Object(object); + while (++index < length) { + var source = sources[index]; + if (source) { + assigner(object, source, index, customizer); + } + } + return object; + }); + } + + /** + * Creates a `baseEach` or `baseEachRight` function. + * + * @private + * @param {Function} eachFunc The function to iterate over a collection. + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseEach(eachFunc, fromRight) { + return function(collection, iteratee) { + if (collection == null) { + return collection; + } + if (!isArrayLike(collection)) { + return eachFunc(collection, iteratee); + } + var length = collection.length, + index = fromRight ? length : -1, + iterable = Object(collection); + + while ((fromRight ? index-- : ++index < length)) { + if (iteratee(iterable[index], index, iterable) === false) { + break; + } + } + return collection; + }; + } + + /** + * Creates a base function for methods like `_.forIn` and `_.forOwn`. + * + * @private + * @param {boolean} [fromRight] Specify iterating from right to left. + * @returns {Function} Returns the new base function. + */ + function createBaseFor(fromRight) { + return function(object, iteratee, keysFunc) { + var index = -1, + iterable = Object(object), + props = keysFunc(object), + length = props.length; + + while (length--) { + var key = props[fromRight ? length : ++index]; + if (iteratee(iterable[key], key, iterable) === false) { + break; + } + } + return object; + }; + } + + /** + * 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 wrapped function. + */ + function createCtor(Ctor) { + return function() { + // Use a `switch` statement to work with class constructors. See + // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist + // for more details. + var args = arguments; + var thisBinding = baseCreate(Ctor.prototype), + result = Ctor.apply(thisBinding, args); + + // Mimic the constructor's `return` behavior. + // See https://es5.github.io/#x13.2.2 for more details. + return isObject(result) ? result : thisBinding; + }; + } + + /** + * Creates a `_.find` or `_.findLast` function. + * + * @private + * @param {Function} findIndexFunc The function to find the collection index. + * @returns {Function} Returns the new find function. + */ + function createFind(findIndexFunc) { + return function(collection, predicate, fromIndex) { + var iterable = Object(collection); + if (!isArrayLike(collection)) { + var iteratee = baseIteratee(predicate, 3); + collection = keys(collection); + predicate = function(key) { return iteratee(iterable[key], key, iterable); }; + } + var index = findIndexFunc(collection, predicate, fromIndex); + return index > -1 ? iterable[iteratee ? collection[index] : index] : undefined; + }; + } + + /** + * Creates a function that wraps `func` to invoke it with the `this` binding + * of `thisArg` and `partials` prepended to the arguments it receives. + * + * @private + * @param {Function} func The function to wrap. + * @param {number} bitmask The bitmask flags. See `createWrap` for more details. + * @param {*} thisArg The `this` binding of `func`. + * @param {Array} partials The arguments to prepend to those provided to + * the new function. + * @returns {Function} Returns the new wrapped function. + */ + function createPartial(func, bitmask, thisArg, partials) { + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + var isBind = bitmask & WRAP_BIND_FLAG, + Ctor = createCtor(func); + + function wrapper() { + var argsIndex = -1, + argsLength = arguments.length, + leftIndex = -1, + leftLength = partials.length, + args = Array(leftLength + argsLength), + fn = (this && this !== root && this instanceof wrapper) ? Ctor : func; + + while (++leftIndex < leftLength) { + args[leftIndex] = partials[leftIndex]; + } + while (argsLength--) { + args[leftIndex++] = arguments[++argsIndex]; + } + return fn.apply(isBind ? thisArg : this, args); + } + return wrapper; + } + + /** + * A specialized version of `baseIsEqualDeep` for arrays with support for + * partial deep comparisons. + * + * @private + * @param {Array} array The array to compare. + * @param {Array} other The other array to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `array` and `other` objects. + * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`. + */ + function equalArrays(array, other, bitmask, customizer, equalFunc, stack) { + var isPartial = bitmask & COMPARE_PARTIAL_FLAG, + arrLength = array.length, + othLength = other.length; + + if (arrLength != othLength && !(isPartial && othLength > arrLength)) { + return false; + } + var index = -1, + result = true, + seen = (bitmask & COMPARE_UNORDERED_FLAG) ? [] : undefined; + + // Ignore non-index properties. + while (++index < arrLength) { + var arrValue = array[index], + othValue = other[index]; + + var compared; + if (compared !== undefined) { + if (compared) { + continue; + } + result = false; + break; + } + // Recursively compare arrays (susceptible to call stack limits). + if (seen) { + if (!baseSome(other, function(othValue, othIndex) { + if (!indexOf(seen, othIndex) && + (arrValue === othValue || equalFunc(arrValue, othValue, bitmask, customizer, stack))) { + return seen.push(othIndex); + } + })) { + result = false; + break; + } + } else if (!( + arrValue === othValue || + equalFunc(arrValue, othValue, bitmask, customizer, stack) + )) { + result = false; + break; + } + } + return result; + } + + /** + * A specialized version of `baseIsEqualDeep` for comparing objects of + * the same `toStringTag`. + * + * **Note:** This function only supports comparing values with tags of + * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {string} tag The `toStringTag` of the objects to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) { + switch (tag) { + + case boolTag: + case dateTag: + case numberTag: + // Coerce booleans to `1` or `0` and dates to milliseconds. + // Invalid dates are coerced to `NaN`. + return eq(+object, +other); + + case errorTag: + return object.name == other.name && object.message == other.message; + + case regexpTag: + case stringTag: + // Coerce regexes to strings and treat strings, primitives and objects, + // as equal. See http://www.ecma-international.org/ecma-262/7.0/#sec-regexp.prototype.tostring + // for more details. + return object == (other + ''); + + } + return false; + } + + /** + * A specialized version of `baseIsEqualDeep` for objects with support for + * partial deep comparisons. + * + * @private + * @param {Object} object The object to compare. + * @param {Object} other The other object to compare. + * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details. + * @param {Function} customizer The function to customize comparisons. + * @param {Function} equalFunc The function to determine equivalents of values. + * @param {Object} stack Tracks traversed `object` and `other` objects. + * @returns {boolean} Returns `true` if the objects are equivalent, else `false`. + */ + function equalObjects(object, other, bitmask, customizer, equalFunc, stack) { + var isPartial = bitmask & COMPARE_PARTIAL_FLAG, + objProps = keys(object), + objLength = objProps.length, + othProps = keys(other), + othLength = othProps.length; + + if (objLength != othLength && !isPartial) { + return false; + } + var index = objLength; + while (index--) { + var key = objProps[index]; + if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) { + return false; + } + } + var result = true; + + var skipCtor = isPartial; + while (++index < objLength) { + key = objProps[index]; + var objValue = object[key], + othValue = other[key]; + + var compared; + // Recursively compare objects (susceptible to call stack limits). + if (!(compared === undefined + ? (objValue === othValue || equalFunc(objValue, othValue, bitmask, customizer, stack)) + : compared + )) { + result = false; + break; + } + skipCtor || (skipCtor = key == 'constructor'); + } + if (result && !skipCtor) { + var objCtor = object.constructor, + othCtor = other.constructor; + + // Non `Object` object instances with different constructors are not equal. + if (objCtor != othCtor && + ('constructor' in object && 'constructor' in other) && + !(typeof objCtor == 'function' && objCtor instanceof objCtor && + typeof othCtor == 'function' && othCtor instanceof othCtor)) { + result = false; + } + } + return result; + } + + /** + * A specialized version of `baseRest` which flattens the rest array. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @returns {Function} Returns the new function. + */ + function flatRest(func) { + return setToString(overRest(func, undefined, flatten), func + ''); + } + + /** + * Checks if `value` is a flattenable `arguments` object or array. + * + * @private + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is flattenable, else `false`. + */ + function isFlattenable(value) { + return isArray(value) || isArguments(value); + } + + /** + * Checks if `value` is a valid array-like index. + * + * @private + * @param {*} value The value to check. + * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index. + * @returns {boolean} Returns `true` if `value` is a valid index, else `false`. + */ + function isIndex(value, length) { + var type = typeof value; + length = length == null ? MAX_SAFE_INTEGER : length; + + return !!length && + (type == 'number' || + (type != 'symbol' && reIsUint.test(value))) && + (value > -1 && value % 1 == 0 && value < length); + } + + /** + * Checks if the given 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) { + if (!isObject(object)) { + return false; + } + var type = typeof index; + if (type == 'number' + ? (isArrayLike(object) && isIndex(index, object.length)) + : (type == 'string' && index in object) + ) { + return eq(object[index], value); + } + return false; + } + + /** + * This function is like + * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys) + * except that it includes inherited enumerable properties. + * + * @private + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + */ + function nativeKeysIn(object) { + var result = []; + if (object != null) { + for (var key in Object(object)) { + result.push(key); + } + } + return result; + } + + /** + * Converts `value` to a string using `Object.prototype.toString`. + * + * @private + * @param {*} value The value to convert. + * @returns {string} Returns the converted string. + */ + function objectToString(value) { + return nativeObjectToString.call(value); + } + + /** + * A specialized version of `baseRest` which transforms the rest array. + * + * @private + * @param {Function} func The function to apply a rest parameter to. + * @param {number} [start=func.length-1] The start position of the rest parameter. + * @param {Function} transform The rest array transform. + * @returns {Function} Returns the new function. + */ + function overRest(func, start, transform) { + start = nativeMax(start === undefined ? (func.length - 1) : start, 0); + return function() { + var args = arguments, + index = -1, + length = nativeMax(args.length - start, 0), + array = Array(length); + + while (++index < length) { + array[index] = args[start + index]; + } + index = -1; + var otherArgs = Array(start + 1); + while (++index < start) { + otherArgs[index] = args[index]; + } + otherArgs[start] = transform(array); + return func.apply(this, otherArgs); + }; + } + + /** + * Sets the `toString` method of `func` to return `string`. + * + * @private + * @param {Function} func The function to modify. + * @param {Function} string The `toString` result. + * @returns {Function} Returns `func`. + */ + var setToString = identity; + + /*------------------------------------------------------------------------*/ + + /** + * Creates an array with all falsey values removed. The values `false`, `null`, + * `0`, `""`, `undefined`, and `NaN` are falsey. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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) { + return baseFilter(array, Boolean); + } + + /** + * Creates a new array concatenating `array` with any additional arrays + * and/or values. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Array + * @param {Array} array The array to concatenate. + * @param {...*} [values] The values to concatenate. + * @returns {Array} Returns the new concatenated array. + * @example + * + * var array = [1]; + * var other = _.concat(array, 2, [3], [[4]]); + * + * console.log(other); + * // => [1, 2, 3, [4]] + * + * console.log(array); + * // => [1] + */ + function concat() { + var length = arguments.length; + if (!length) { + return []; + } + var args = Array(length - 1), + array = arguments[0], + index = length; + + while (index--) { + args[index - 1] = arguments[index]; + } + return arrayPush(isArray(array) ? copyArray(array) : [array], baseFlatten(args, 1)); + } + + /** + * This method is like `_.find` except that it returns the index of the first + * element `predicate` returns truthy for instead of the element itself. + * + * @static + * @memberOf _ + * @since 1.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=0] The index to search from. + * @returns {number} Returns the index of the found element, else `-1`. + * @example + * + * var users = [ + * { 'user': 'barney', 'active': false }, + * { 'user': 'fred', 'active': false }, + * { 'user': 'pebbles', 'active': true } + * ]; + * + * _.findIndex(users, function(o) { return o.user == 'barney'; }); + * // => 0 + * + * // The `_.matches` iteratee shorthand. + * _.findIndex(users, { 'user': 'fred', 'active': false }); + * // => 1 + * + * // The `_.matchesProperty` iteratee shorthand. + * _.findIndex(users, ['active', false]); + * // => 0 + * + * // The `_.property` iteratee shorthand. + * _.findIndex(users, 'active'); + * // => 2 + */ + function findIndex(array, predicate, fromIndex) { + var length = array == null ? 0 : array.length; + if (!length) { + return -1; + } + var index = fromIndex == null ? 0 : toInteger(fromIndex); + if (index < 0) { + index = nativeMax(length + index, 0); + } + return baseFindIndex(array, baseIteratee(predicate, 3), index); + } + + /** + * Flattens `array` a single level deep. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flatten([1, [2, [3, [4]], 5]]); + * // => [1, 2, [3, [4]], 5] + */ + function flatten(array) { + var length = array == null ? 0 : array.length; + return length ? baseFlatten(array, 1) : []; + } + + /** + * Recursively flattens `array`. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to flatten. + * @returns {Array} Returns the new flattened array. + * @example + * + * _.flattenDeep([1, [2, [3, [4]], 5]]); + * // => [1, 2, 3, 4, 5] + */ + function flattenDeep(array) { + var length = array == null ? 0 : array.length; + return length ? baseFlatten(array, INFINITY) : []; + } + + /** + * Gets the first element of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @alias first + * @category Array + * @param {Array} array The array to query. + * @returns {*} Returns the first element of `array`. + * @example + * + * _.head([1, 2, 3]); + * // => 1 + * + * _.head([]); + * // => undefined + */ + function head(array) { + return (array && array.length) ? array[0] : undefined; + } + + /** + * Gets the index at which the first occurrence of `value` is found in `array` + * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * for equality comparisons. If `fromIndex` is negative, it's used as the + * offset from the end of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Array + * @param {Array} array The array to inspect. + * @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`. + * @example + * + * _.indexOf([1, 2, 1, 2], 2); + * // => 1 + * + * // Search from the `fromIndex`. + * _.indexOf([1, 2, 1, 2], 2, 2); + * // => 3 + */ + function indexOf(array, value, fromIndex) { + var length = array == null ? 0 : array.length; + if (typeof fromIndex == 'number') { + fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : fromIndex; + } else { + fromIndex = 0; + } + var index = (fromIndex || 0) - 1, + isReflexive = value === value; + + while (++index < length) { + var other = array[index]; + if ((isReflexive ? other === value : other !== other)) { + return index; + } + } + return -1; + } + + /** + * Gets the last element of `array`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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) { + var length = array == null ? 0 : array.length; + return length ? array[length - 1] : undefined; + } + + /** + * Creates a slice of `array` from `start` up to, but not including, `end`. + * + * **Note:** This method is used instead of + * [`Array#slice`](https://mdn.io/Array/slice) to ensure dense arrays are + * returned. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Array + * @param {Array} array The array to slice. + * @param {number} [start=0] The start position. + * @param {number} [end=array.length] The end position. + * @returns {Array} Returns the slice of `array`. + */ + function slice(array, start, end) { + var length = array == null ? 0 : array.length; + start = start == null ? 0 : +start; + end = end === undefined ? length : +end; + return length ? baseSlice(array, start, end) : []; + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates a `lodash` wrapper instance that wraps `value` with explicit method + * chain sequences enabled. The result of such sequences must be unwrapped + * with `_#value`. + * + * @static + * @memberOf _ + * @since 1.3.0 + * @category Seq + * @param {*} value The value to wrap. + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'pebbles', 'age': 1 } + * ]; + * + * var youngest = _ + * .chain(users) + * .sortBy('age') + * .map(function(o) { + * return o.user + ' is ' + o.age; + * }) + * .head() + * .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 invoked with one argument; (value). The purpose of this method is to + * "tap into" a method chain sequence in order to modify intermediate results. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns `value`. + * @example + * + * _([1, 2, 3]) + * .tap(function(array) { + * // Mutate input array. + * array.pop(); + * }) + * .reverse() + * .value(); + * // => [2, 1] + */ + function tap(value, interceptor) { + interceptor(value); + return value; + } + + /** + * This method is like `_.tap` except that it returns the result of `interceptor`. + * The purpose of this method is to "pass thru" values replacing intermediate + * results in a method chain sequence. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Seq + * @param {*} value The value to provide to `interceptor`. + * @param {Function} interceptor The function to invoke. + * @returns {*} Returns the result of `interceptor`. + * @example + * + * _(' abc ') + * .chain() + * .trim() + * .thru(function(value) { + * return [value]; + * }) + * .value(); + * // => ['abc'] + */ + function thru(value, interceptor) { + return interceptor(value); + } + + /** + * Creates a `lodash` wrapper instance with explicit method chain sequences enabled. + * + * @name chain + * @memberOf _ + * @since 0.1.0 + * @category Seq + * @returns {Object} Returns the new `lodash` wrapper instance. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 } + * ]; + * + * // A sequence without explicit chaining. + * _(users).head(); + * // => { 'user': 'barney', 'age': 36 } + * + * // A sequence with explicit chaining. + * _(users) + * .chain() + * .head() + * .pick('user') + * .value(); + * // => { 'user': 'barney' } + */ + function wrapperChain() { + return chain(this); + } + + /** + * Executes the chain sequence to resolve the unwrapped value. + * + * @name value + * @memberOf _ + * @since 0.1.0 + * @alias toJSON, valueOf + * @category Seq + * @returns {*} Returns the resolved unwrapped value. + * @example + * + * _([1, 2, 3]).value(); + * // => [1, 2, 3] + */ + function wrapperValue() { + return baseWrapperValue(this.__wrapped__, this.__actions__); + } + + /*------------------------------------------------------------------------*/ + + /** + * Checks if `predicate` returns truthy for **all** elements of `collection`. + * Iteration is stopped once `predicate` returns falsey. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * **Note:** This method returns `true` for + * [empty collections](https://en.wikipedia.org/wiki/Empty_set) because + * [everything is true](https://en.wikipedia.org/wiki/Vacuous_truth) of + * elements of empty collections. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @returns {boolean} Returns `true` if all elements pass the predicate check, + * else `false`. + * @example + * + * _.every([true, 1, null, 'yes'], Boolean); + * // => false + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': false }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.every(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.every(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.every(users, 'active'); + * // => false + */ + function every(collection, predicate, guard) { + predicate = guard ? undefined : predicate; + return baseEvery(collection, baseIteratee(predicate)); + } + + /** + * Iterates over elements of `collection`, returning an array of all elements + * `predicate` returns truthy for. The predicate is invoked with three + * arguments: (value, index|key, collection). + * + * **Note:** Unlike `_.remove`, this method returns a new array. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new filtered array. + * @see _.reject + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * _.filter(users, function(o) { return !o.active; }); + * // => objects for ['fred'] + * + * // The `_.matches` iteratee shorthand. + * _.filter(users, { 'age': 36, 'active': true }); + * // => objects for ['barney'] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.filter(users, ['active', false]); + * // => objects for ['fred'] + * + * // The `_.property` iteratee shorthand. + * _.filter(users, 'active'); + * // => objects for ['barney'] + */ + function filter(collection, predicate) { + return baseFilter(collection, baseIteratee(predicate)); + } + + /** + * Iterates over elements of `collection`, returning the first element + * `predicate` returns truthy for. The predicate is invoked with three + * arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to inspect. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param {number} [fromIndex=0] The index to search from. + * @returns {*} Returns the matched element, else `undefined`. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false }, + * { 'user': 'pebbles', 'age': 1, 'active': true } + * ]; + * + * _.find(users, function(o) { return o.age < 40; }); + * // => object for 'barney' + * + * // The `_.matches` iteratee shorthand. + * _.find(users, { 'age': 1, 'active': true }); + * // => object for 'pebbles' + * + * // The `_.matchesProperty` iteratee shorthand. + * _.find(users, ['active', false]); + * // => object for 'fred' + * + * // The `_.property` iteratee shorthand. + * _.find(users, 'active'); + * // => object for 'barney' + */ + var find = createFind(findIndex); + + /** + * Iterates over elements of `collection` and invokes `iteratee` for each element. + * The iteratee is invoked with three arguments: (value, index|key, collection). + * Iteratee 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 use `_.forIn` + * or `_.forOwn` for object iteration. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @alias each + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array|Object} Returns `collection`. + * @see _.forEachRight + * @example + * + * _.forEach([1, 2], function(value) { + * console.log(value); + * }); + * // => Logs `1` then `2`. + * + * _.forEach({ 'a': 1, 'b': 2 }, function(value, key) { + * console.log(key); + * }); + * // => Logs 'a' then 'b' (iteration order is not guaranteed). + */ + function forEach(collection, iteratee) { + return baseEach(collection, baseIteratee(iteratee)); + } + + /** + * Creates an array of values by running each element in `collection` thru + * `iteratee`. The iteratee is invoked with three arguments: + * (value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`. + * + * The guarded methods are: + * `ary`, `chunk`, `curry`, `curryRight`, `drop`, `dropRight`, `every`, + * `fill`, `invert`, `parseInt`, `random`, `range`, `rangeRight`, `repeat`, + * `sampleSize`, `slice`, `some`, `sortBy`, `split`, `take`, `takeRight`, + * `template`, `trim`, `trimEnd`, `trimStart`, and `words` + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @returns {Array} Returns the new mapped array. + * @example + * + * function square(n) { + * return n * n; + * } + * + * _.map([4, 8], square); + * // => [16, 64] + * + * _.map({ 'a': 4, 'b': 8 }, square); + * // => [16, 64] (iteration order is not guaranteed) + * + * var users = [ + * { 'user': 'barney' }, + * { 'user': 'fred' } + * ]; + * + * // The `_.property` iteratee shorthand. + * _.map(users, 'user'); + * // => ['barney', 'fred'] + */ + function map(collection, iteratee) { + return baseMap(collection, baseIteratee(iteratee)); + } + + /** + * Reduces `collection` to a value which is the accumulated result of running + * each element in `collection` thru `iteratee`, where each successive + * invocation is supplied the return value of the previous. If `accumulator` + * is not given, the first element of `collection` is used as the initial + * value. The iteratee is invoked with four arguments: + * (accumulator, value, index|key, collection). + * + * Many lodash methods are guarded to work as iteratees for methods like + * `_.reduce`, `_.reduceRight`, and `_.transform`. + * + * The guarded methods are: + * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`, + * and `sortBy` + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [iteratee=_.identity] The function invoked per iteration. + * @param {*} [accumulator] The initial value. + * @returns {*} Returns the accumulated value. + * @see _.reduceRight + * @example + * + * _.reduce([1, 2], function(sum, n) { + * return sum + n; + * }, 0); + * // => 3 + * + * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { + * (result[value] || (result[value] = [])).push(key); + * return result; + * }, {}); + * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed) + */ + function reduce(collection, iteratee, accumulator) { + return baseReduce(collection, baseIteratee(iteratee), accumulator, arguments.length < 3, baseEach); + } + + /** + * Gets the size of `collection` by returning its length for array-like + * values or the number of own enumerable string keyed properties for objects. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object|string} collection The collection to inspect. + * @returns {number} Returns the collection size. + * @example + * + * _.size([1, 2, 3]); + * // => 3 + * + * _.size({ 'a': 1, 'b': 2 }); + * // => 2 + * + * _.size('pebbles'); + * // => 7 + */ + function size(collection) { + if (collection == null) { + return 0; + } + collection = isArrayLike(collection) ? collection : nativeKeys(collection); + return collection.length; + } + + /** + * Checks if `predicate` returns truthy for **any** element of `collection`. + * Iteration is stopped once `predicate` returns truthy. The predicate is + * invoked with three arguments: (value, index|key, collection). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {Function} [predicate=_.identity] The function invoked per iteration. + * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`. + * @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', 'active': true }, + * { 'user': 'fred', 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.some(users, { 'user': 'barney', 'active': false }); + * // => false + * + * // The `_.matchesProperty` iteratee shorthand. + * _.some(users, ['active', false]); + * // => true + * + * // The `_.property` iteratee shorthand. + * _.some(users, 'active'); + * // => true + */ + function some(collection, predicate, guard) { + predicate = guard ? undefined : predicate; + return baseSome(collection, baseIteratee(predicate)); + } + + /** + * Creates an array of elements, sorted in ascending order by the results of + * running each element in a collection thru each iteratee. This method + * performs a stable sort, that is, it preserves the original sort order of + * equal elements. The iteratees are invoked with one argument: (value). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Collection + * @param {Array|Object} collection The collection to iterate over. + * @param {...(Function|Function[])} [iteratees=[_.identity]] + * The iteratees to sort by. + * @returns {Array} Returns the new sorted array. + * @example + * + * var users = [ + * { 'user': 'fred', 'age': 48 }, + * { 'user': 'barney', 'age': 36 }, + * { 'user': 'fred', 'age': 40 }, + * { 'user': 'barney', 'age': 34 } + * ]; + * + * _.sortBy(users, [function(o) { return o.user; }]); + * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]] + * + * _.sortBy(users, ['user', 'age']); + * // => objects for [['barney', 34], ['barney', 36], ['fred', 40], ['fred', 48]] + */ + function sortBy(collection, iteratee) { + var index = 0; + iteratee = baseIteratee(iteratee); + + return baseMap(baseMap(collection, function(value, key, collection) { + return { 'value': value, 'index': index++, 'criteria': iteratee(value, key, collection) }; + }).sort(function(object, other) { + return compareAscending(object.criteria, other.criteria) || (object.index - other.index); + }), baseProperty('value')); + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates a function that invokes `func`, with the `this` binding and arguments + * of the created function, while it's called less than `n` times. Subsequent + * calls to the created function return the result of the last `func` invocation. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @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(element).on('click', _.before(5, addContactToList)); + * // => Allows adding up to 4 contacts to the list. + */ + function before(n, func) { + var result; + if (typeof func != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + n = toInteger(n); + return function() { + if (--n > 0) { + result = func.apply(this, arguments); + } + if (n <= 1) { + func = undefined; + } + return result; + }; + } + + /** + * Creates a function that invokes `func` with the `this` binding of `thisArg` + * and `partials` prepended to the arguments it receives. + * + * The `_.bind.placeholder` value, which defaults to `_` in monolithic builds, + * may be used as a placeholder for partially applied arguments. + * + * **Note:** Unlike native `Function#bind`, this method doesn't set the "length" + * property of bound functions. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to bind. + * @param {*} thisArg The `this` binding of `func`. + * @param {...*} [partials] The arguments to be partially applied. + * @returns {Function} Returns the new bound function. + * @example + * + * function greet(greeting, punctuation) { + * return greeting + ' ' + this.user + punctuation; + * } + * + * var object = { 'user': 'fred' }; + * + * var bound = _.bind(greet, object, 'hi'); + * bound('!'); + * // => 'hi fred!' + * + * // Bound with placeholders. + * var bound = _.bind(greet, object, _, '!'); + * bound('hi'); + * // => 'hi fred!' + */ + var bind = baseRest(function(func, thisArg, partials) { + return createPartial(func, WRAP_BIND_FLAG | WRAP_PARTIAL_FLAG, thisArg, partials); + }); + + /** + * Defers invoking the `func` until the current call stack has cleared. Any + * additional arguments are provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to defer. + * @param {...*} [args] The arguments to invoke `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.defer(function(text) { + * console.log(text); + * }, 'deferred'); + * // => Logs 'deferred' after one millisecond. + */ + var defer = baseRest(function(func, args) { + return baseDelay(func, 1, args); + }); + + /** + * Invokes `func` after `wait` milliseconds. Any additional arguments are + * provided to `func` when it's invoked. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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 `func` with. + * @returns {number} Returns the timer id. + * @example + * + * _.delay(function(text) { + * console.log(text); + * }, 1000, 'later'); + * // => Logs 'later' after one second. + */ + var delay = baseRest(function(func, wait, args) { + return baseDelay(func, toNumber(wait) || 0, args); + }); + + /** + * 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 _ + * @since 3.0.0 + * @category Function + * @param {Function} predicate The predicate to negate. + * @returns {Function} Returns the new negated 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 (typeof predicate != 'function') { + throw new TypeError(FUNC_ERROR_TEXT); + } + return function() { + var args = arguments; + return !predicate.apply(this, args); + }; + } + + /** + * Creates a function that is restricted to invoking `func` once. Repeat calls + * to the function return the value of the first invocation. The `func` is + * invoked with the `this` binding and arguments of the created function. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Function + * @param {Function} func The function to restrict. + * @returns {Function} Returns the new restricted function. + * @example + * + * var initialize = _.once(createApplication); + * initialize(); + * initialize(); + * // => `createApplication` is invoked once + */ + function once(func) { + return before(2, func); + } + + /*------------------------------------------------------------------------*/ + + /** + * Creates a shallow clone of `value`. + * + * **Note:** This method is loosely based on the + * [structured clone algorithm](https://mdn.io/Structured_clone_algorithm) + * and supports cloning arrays, array buffers, booleans, date objects, maps, + * numbers, `Object` objects, regexes, sets, strings, symbols, and typed + * arrays. The own enumerable properties of `arguments` objects are cloned + * as plain objects. An empty object is returned for uncloneable values such + * as error objects, functions, DOM nodes, and WeakMaps. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to clone. + * @returns {*} Returns the cloned value. + * @see _.cloneDeep + * @example + * + * var objects = [{ 'a': 1 }, { 'b': 2 }]; + * + * var shallow = _.clone(objects); + * console.log(shallow[0] === objects[0]); + * // => true + */ + function clone(value) { + if (!isObject(value)) { + return value; + } + return isArray(value) ? copyArray(value) : copyObject(value, nativeKeys(value)); + } + + /** + * Performs a + * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) + * comparison between two values to determine if they are equivalent. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'a': 1 }; + * var other = { 'a': 1 }; + * + * _.eq(object, object); + * // => true + * + * _.eq(object, other); + * // => false + * + * _.eq('a', 'a'); + * // => true + * + * _.eq('a', Object('a')); + * // => false + * + * _.eq(NaN, NaN); + * // => true + */ + function eq(value, other) { + return value === other || (value !== value && other !== other); + } + + /** + * Checks if `value` is likely an `arguments` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an `arguments` object, + * else `false`. + * @example + * + * _.isArguments(function() { return arguments; }()); + * // => true + * + * _.isArguments([1, 2, 3]); + * // => false + */ + var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) { + return isObjectLike(value) && hasOwnProperty.call(value, 'callee') && + !propertyIsEnumerable.call(value, 'callee'); + }; + + /** + * Checks if `value` is classified as an `Array` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is an array, else `false`. + * @example + * + * _.isArray([1, 2, 3]); + * // => true + * + * _.isArray(document.body.children); + * // => false + * + * _.isArray('abc'); + * // => false + * + * _.isArray(_.noop); + * // => false + */ + var isArray = Array.isArray; + + /** + * Checks if `value` is array-like. A value is considered array-like if it's + * not a function and has a `value.length` that's an integer greater than or + * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is array-like, else `false`. + * @example + * + * _.isArrayLike([1, 2, 3]); + * // => true + * + * _.isArrayLike(document.body.children); + * // => true + * + * _.isArrayLike('abc'); + * // => true + * + * _.isArrayLike(_.noop); + * // => false + */ + function isArrayLike(value) { + return value != null && isLength(value.length) && !isFunction(value); + } + + /** + * Checks if `value` is classified as a boolean primitive or object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a boolean, else `false`. + * @example + * + * _.isBoolean(false); + * // => true + * + * _.isBoolean(null); + * // => false + */ + function isBoolean(value) { + return value === true || value === false || + (isObjectLike(value) && baseGetTag(value) == boolTag); + } + + /** + * Checks if `value` is classified as a `Date` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a date object, else `false`. + * @example + * + * _.isDate(new Date); + * // => true + * + * _.isDate('Mon April 23 2012'); + * // => false + */ + var isDate = baseIsDate; + + /** + * Checks if `value` is an empty object, collection, map, or set. + * + * Objects are considered empty if they have no own enumerable string keyed + * properties. + * + * Array-like values such as `arguments` objects, arrays, buffers, strings, or + * jQuery-like collections are considered empty if they have a `length` of `0`. + * Similarly, maps and sets are considered empty if they have a `size` of `0`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @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 (isArrayLike(value) && + (isArray(value) || isString(value) || + isFunction(value.splice) || isArguments(value))) { + return !value.length; + } + return !nativeKeys(value).length; + } + + /** + * Performs a deep comparison between two values to determine if they are + * equivalent. + * + * **Note:** This method supports comparing arrays, array buffers, booleans, + * date objects, error objects, maps, numbers, `Object` objects, regexes, + * sets, strings, symbols, and typed arrays. `Object` objects are compared + * by their own, not inherited, enumerable properties. Functions and DOM + * nodes are compared by strict equality, i.e. `===`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to compare. + * @param {*} other The other value to compare. + * @returns {boolean} Returns `true` if the values are equivalent, else `false`. + * @example + * + * var object = { 'a': 1 }; + * var other = { 'a': 1 }; + * + * _.isEqual(object, other); + * // => true + * + * object === other; + * // => false + */ + function isEqual(value, other) { + return baseIsEqual(value, other); + } + + /** + * Checks if `value` is a finite primitive number. + * + * **Note:** This method is based on + * [`Number.isFinite`](https://mdn.io/Number/isFinite). + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a finite number, else `false`. + * @example + * + * _.isFinite(3); + * // => true + * + * _.isFinite(Number.MIN_VALUE); + * // => true + * + * _.isFinite(Infinity); + * // => false + * + * _.isFinite('3'); + * // => false + */ + function isFinite(value) { + return typeof value == 'number' && nativeIsFinite(value); + } + + /** + * Checks if `value` is classified as a `Function` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a function, else `false`. + * @example + * + * _.isFunction(_); + * // => true + * + * _.isFunction(/abc/); + * // => false + */ + function isFunction(value) { + if (!isObject(value)) { + return false; + } + // The use of `Object#toString` avoids issues with the `typeof` operator + // in Safari 9 which returns 'object' for typed arrays and other constructors. + var tag = baseGetTag(value); + return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag; + } + + /** + * Checks if `value` is a valid array-like length. + * + * **Note:** This method is loosely based on + * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a valid length, else `false`. + * @example + * + * _.isLength(3); + * // => true + * + * _.isLength(Number.MIN_VALUE); + * // => false + * + * _.isLength(Infinity); + * // => false + * + * _.isLength('3'); + * // => false + */ + function isLength(value) { + return typeof value == 'number' && + value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER; + } + + /** + * Checks if `value` is the + * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types) + * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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(_.noop); + * // => true + * + * _.isObject(null); + * // => false + */ + function isObject(value) { + var type = typeof value; + return value != null && (type == 'object' || type == 'function'); + } + + /** + * Checks if `value` is object-like. A value is object-like if it's not `null` + * and has a `typeof` result of "object". + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is object-like, else `false`. + * @example + * + * _.isObjectLike({}); + * // => true + * + * _.isObjectLike([1, 2, 3]); + * // => true + * + * _.isObjectLike(_.noop); + * // => false + * + * _.isObjectLike(null); + * // => false + */ + function isObjectLike(value) { + return value != null && typeof value == 'object'; + } + + /** + * Checks if `value` is `NaN`. + * + * **Note:** This method is based on + * [`Number.isNaN`](https://mdn.io/Number/isNaN) and is not the same as + * global [`isNaN`](https://mdn.io/isNaN) which returns `true` for + * `undefined` and other non-number values. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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) { + // An `NaN` primitive is the only value that is not equal to itself. + // Perform the `toStringTag` check first to avoid errors with some + // ActiveX objects in IE. + return isNumber(value) && value != +value; + } + + /** + * Checks if `value` is `null`. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @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 _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a number, else `false`. + * @example + * + * _.isNumber(3); + * // => true + * + * _.isNumber(Number.MIN_VALUE); + * // => true + * + * _.isNumber(Infinity); + * // => true + * + * _.isNumber('3'); + * // => false + */ + function isNumber(value) { + return typeof value == 'number' || + (isObjectLike(value) && baseGetTag(value) == numberTag); + } + + /** + * Checks if `value` is classified as a `RegExp` object. + * + * @static + * @memberOf _ + * @since 0.1.0 + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a regexp, else `false`. + * @example + * + * _.isRegExp(/abc/); + * // => true + * + * _.isRegExp('/abc/'); + * // => false + */ + var isRegExp = baseIsRegExp; + + /** + * Checks if `value` is classified as a `String` primitive or object. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Lang + * @param {*} value The value to check. + * @returns {boolean} Returns `true` if `value` is a string, else `false`. + * @example + * + * _.isString('abc'); + * // => true + * + * _.isString(1); + * // => false + */ + function isString(value) { + return typeof value == 'string' || + (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag); + } + + /** + * Checks if `value` is `undefined`. + * + * @static + * @since 0.1.0 + * @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 value === undefined; + } + + /** + * Converts `value` to an array. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Lang + * @param {*} value The value to convert. + * @returns {Array} Returns the converted array. + * @example + * + * _.toArray({ 'a': 1, 'b': 2 }); + * // => [1, 2] + * + * _.toArray('abc'); + * // => ['a', 'b', 'c'] + * + * _.toArray(1); + * // => [] + * + * _.toArray(null); + * // => [] + */ + function toArray(value) { + if (!isArrayLike(value)) { + return values(value); + } + return value.length ? copyArray(value) : []; + } + + /** + * Converts `value` to an integer. + * + * **Note:** This method is loosely based on + * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger). + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {number} Returns the converted integer. + * @example + * + * _.toInteger(3.2); + * // => 3 + * + * _.toInteger(Number.MIN_VALUE); + * // => 0 + * + * _.toInteger(Infinity); + * // => 1.7976931348623157e+308 + * + * _.toInteger('3.2'); + * // => 3 + */ + var toInteger = Number; + + /** + * Converts `value` to a number. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to process. + * @returns {number} Returns the number. + * @example + * + * _.toNumber(3.2); + * // => 3.2 + * + * _.toNumber(Number.MIN_VALUE); + * // => 5e-324 + * + * _.toNumber(Infinity); + * // => Infinity + * + * _.toNumber('3.2'); + * // => 3.2 + */ + var toNumber = Number; + + /** + * Converts `value` to a string. An empty string is returned for `null` + * and `undefined` values. The sign of `-0` is preserved. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @category Lang + * @param {*} value The value to convert. + * @returns {string} Returns the converted string. + * @example + * + * _.toString(null); + * // => '' + * + * _.toString(-0); + * // => '-0' + * + * _.toString([1, 2, 3]); + * // => '1,2,3' + */ + function toString(value) { + if (typeof value == 'string') { + return value; + } + return value == null ? '' : (value + ''); + } + + /*------------------------------------------------------------------------*/ + + /** + * Assigns own enumerable string keyed properties of source objects to the + * destination object. Source objects are applied from left to right. + * Subsequent sources overwrite property assignments of previous sources. + * + * **Note:** This method mutates `object` and is loosely based on + * [`Object.assign`](https://mdn.io/Object/assign). + * + * @static + * @memberOf _ + * @since 0.10.0 + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.assignIn + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * function Bar() { + * this.c = 3; + * } + * + * Foo.prototype.b = 2; + * Bar.prototype.d = 4; + * + * _.assign({ 'a': 0 }, new Foo, new Bar); + * // => { 'a': 1, 'c': 3 } + */ + var assign = createAssigner(function(object, source) { + copyObject(source, nativeKeys(source), object); + }); + + /** + * This method is like `_.assign` except that it iterates over own and + * inherited source properties. + * + * **Note:** This method mutates `object`. + * + * @static + * @memberOf _ + * @since 4.0.0 + * @alias extend + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.assign + * @example + * + * function Foo() { + * this.a = 1; + * } + * + * function Bar() { + * this.c = 3; + * } + * + * Foo.prototype.b = 2; + * Bar.prototype.d = 4; + * + * _.assignIn({ 'a': 0 }, new Foo, new Bar); + * // => { 'a': 1, 'b': 2, 'c': 3, 'd': 4 } + */ + var assignIn = createAssigner(function(object, source) { + copyObject(source, nativeKeysIn(source), object); + }); + + /** + * Creates an object that inherits from the `prototype` object. If a + * `properties` object is given, its own enumerable string keyed properties + * are assigned to the created object. + * + * @static + * @memberOf _ + * @since 2.3.0 + * @category Object + * @param {Object} prototype The object to inherit from. + * @param {Object} [properties] The properties to assign to the object. + * @returns {Object} Returns the new object. + * @example + * + * function Shape() { + * this.x = 0; + * this.y = 0; + * } + * + * function Circle() { + * Shape.call(this); + * } + * + * Circle.prototype = _.create(Shape.prototype, { + * 'constructor': Circle + * }); + * + * var circle = new Circle; + * circle instanceof Circle; + * // => true + * + * circle instanceof Shape; + * // => true + */ + function create(prototype, properties) { + var result = baseCreate(prototype); + return properties == null ? result : assign(result, properties); + } + + /** + * Assigns own and inherited enumerable string keyed properties of source + * objects to the destination object for all destination properties that + * resolve to `undefined`. Source objects are applied from left to right. + * Once a property is set, additional values of the same property are ignored. + * + * **Note:** This method mutates `object`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The destination object. + * @param {...Object} [sources] The source objects. + * @returns {Object} Returns `object`. + * @see _.defaultsDeep + * @example + * + * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 }); + * // => { 'a': 1, 'b': 2 } + */ + var defaults = baseRest(function(object, sources) { + object = Object(object); + + var index = -1; + var length = sources.length; + var guard = length > 2 ? sources[2] : undefined; + + if (guard && isIterateeCall(sources[0], sources[1], guard)) { + length = 1; + } + + while (++index < length) { + var source = sources[index]; + var props = keysIn(source); + var propsIndex = -1; + var propsLength = props.length; + + while (++propsIndex < propsLength) { + var key = props[propsIndex]; + var value = object[key]; + + if (value === undefined || + (eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) { + object[key] = source[key]; + } + } + } + + return object; + }); + + /** + * Checks if `path` is a direct property of `object`. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path to check. + * @returns {boolean} Returns `true` if `path` exists, else `false`. + * @example + * + * var object = { 'a': { 'b': 2 } }; + * var other = _.create({ 'a': _.create({ 'b': 2 }) }); + * + * _.has(object, 'a'); + * // => true + * + * _.has(object, 'a.b'); + * // => true + * + * _.has(object, ['a', 'b']); + * // => true + * + * _.has(other, 'a'); + * // => false + */ + function has(object, path) { + return object != null && hasOwnProperty.call(object, path); + } + + /** + * Creates an array of the own enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. See the + * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys) + * for more details. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keys(new Foo); + * // => ['a', 'b'] (iteration order is not guaranteed) + * + * _.keys('hi'); + * // => ['0', '1'] + */ + var keys = nativeKeys; + + /** + * Creates an array of the own and inherited enumerable property names of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property names. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.keysIn(new Foo); + * // => ['a', 'b', 'c'] (iteration order is not guaranteed) + */ + var keysIn = nativeKeysIn; + + /** + * Creates an object composed of the picked `object` properties. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The source object. + * @param {...(string|string[])} [paths] The property paths to pick. + * @returns {Object} Returns the new object. + * @example + * + * var object = { 'a': 1, 'b': '2', 'c': 3 }; + * + * _.pick(object, ['a', 'c']); + * // => { 'a': 1, 'c': 3 } + */ + var pick = flatRest(function(object, paths) { + return object == null ? {} : basePick(object, paths); + }); + + /** + * This method is like `_.get` except that if the resolved value is a + * function it's invoked with the `this` binding of its parent object and + * its result is returned. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @param {Array|string} path The path of the property to resolve. + * @param {*} [defaultValue] The value returned for `undefined` resolved values. + * @returns {*} Returns the resolved value. + * @example + * + * var object = { 'a': [{ 'b': { 'c1': 3, 'c2': _.constant(4) } }] }; + * + * _.result(object, 'a[0].b.c1'); + * // => 3 + * + * _.result(object, 'a[0].b.c2'); + * // => 4 + * + * _.result(object, 'a[0].b.c3', 'default'); + * // => 'default' + * + * _.result(object, 'a[0].b.c3', _.constant('default')); + * // => 'default' + */ + function result(object, path, defaultValue) { + var value = object == null ? undefined : object[path]; + if (value === undefined) { + value = defaultValue; + } + return isFunction(value) ? value.call(object) : value; + } + + /** + * Creates an array of the own enumerable string keyed property values of `object`. + * + * **Note:** Non-object values are coerced to objects. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Object + * @param {Object} object The object to query. + * @returns {Array} Returns the array of property values. + * @example + * + * function Foo() { + * this.a = 1; + * this.b = 2; + * } + * + * Foo.prototype.c = 3; + * + * _.values(new Foo); + * // => [1, 2] (iteration order is not guaranteed) + * + * _.values('hi'); + * // => ['h', 'i'] + */ + function values(object) { + return object == null ? [] : baseValues(object, keys(object)); + } + + /*------------------------------------------------------------------------*/ + + /** + * 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_](https://mths.be/he). + * + * Though the ">" character is escaped for symmetry, characters like + * ">" and "/" don't need escaping in HTML and have no special meaning + * unless they're part of a tag or unquoted attribute value. See + * [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands) + * (under "semi-related fun fact") for more details. + * + * When working with HTML you should always + * [quote attribute values](http://wonko.com/post/html-escaping) to reduce + * XSS vectors. + * + * @static + * @since 0.1.0 + * @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) { + string = toString(string); + return (string && reHasUnescapedHtml.test(string)) + ? string.replace(reUnescapedHtml, escapeHtmlChar) + : string; + } + + /*------------------------------------------------------------------------*/ + + /** + * This method returns the first argument it receives. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Util + * @param {*} value Any value. + * @returns {*} Returns `value`. + * @example + * + * var object = { 'a': 1 }; + * + * console.log(_.identity(object) === object); + * // => true + */ + function identity(value) { + return value; + } + + /** + * Creates a function that invokes `func` with the arguments of the created + * function. If `func` is a property name, the created function returns the + * property value for a given element. If `func` is an array or object, the + * created function returns `true` for elements that contain the equivalent + * source properties, otherwise it returns `false`. + * + * @static + * @since 4.0.0 + * @memberOf _ + * @category Util + * @param {*} [func=_.identity] The value to convert to a callback. + * @returns {Function} Returns the callback. + * @example + * + * var users = [ + * { 'user': 'barney', 'age': 36, 'active': true }, + * { 'user': 'fred', 'age': 40, 'active': false } + * ]; + * + * // The `_.matches` iteratee shorthand. + * _.filter(users, _.iteratee({ 'user': 'barney', 'active': true })); + * // => [{ 'user': 'barney', 'age': 36, 'active': true }] + * + * // The `_.matchesProperty` iteratee shorthand. + * _.filter(users, _.iteratee(['user', 'fred'])); + * // => [{ 'user': 'fred', 'age': 40 }] + * + * // The `_.property` iteratee shorthand. + * _.map(users, _.iteratee('user')); + * // => ['barney', 'fred'] + * + * // Create custom iteratee shorthands. + * _.iteratee = _.wrap(_.iteratee, function(iteratee, func) { + * return !_.isRegExp(func) ? iteratee(func) : function(string) { + * return func.test(string); + * }; + * }); + * + * _.filter(['abc', 'def'], /ef/); + * // => ['def'] + */ + var iteratee = baseIteratee; + + /** + * Creates a function that performs a partial deep comparison between a given + * object and `source`, returning `true` if the given object has equivalent + * property values, else `false`. + * + * **Note:** The created function is equivalent to `_.isMatch` with `source` + * partially applied. + * + * Partial comparisons will match empty array and empty object `source` + * values against any array or object value, respectively. See `_.isEqual` + * for a list of supported value comparisons. + * + * @static + * @memberOf _ + * @since 3.0.0 + * @category Util + * @param {Object} source The object of property values to match. + * @returns {Function} Returns the new spec function. + * @example + * + * var objects = [ + * { 'a': 1, 'b': 2, 'c': 3 }, + * { 'a': 4, 'b': 5, 'c': 6 } + * ]; + * + * _.filter(objects, _.matches({ 'a': 4, 'c': 6 })); + * // => [{ 'a': 4, 'b': 5, 'c': 6 }] + */ + function matches(source) { + return baseMatches(assign({}, source)); + } + + /** + * Adds all own enumerable string keyed function properties of a source + * object to the destination object. If `object` is a function, then methods + * are added to its prototype as well. + * + * **Note:** Use `_.runInContext` to create a pristine `lodash` function to + * avoid conflicts caused by modifying the original. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Util + * @param {Function|Object} [object=lodash] The destination object. + * @param {Object} source The object of functions to add. + * @param {Object} [options={}] The options object. + * @param {boolean} [options.chain=true] Specify whether mixins are chainable. + * @returns {Function|Object} Returns `object`. + * @example + * + * function vowels(string) { + * return _.filter(string, function(v) { + * return /[aeiou]/i.test(v); + * }); + * } + * + * _.mixin({ 'vowels': vowels }); + * _.vowels('fred'); + * // => ['e'] + * + * _('fred').vowels().value(); + * // => ['e'] + * + * _.mixin({ 'vowels': vowels }, { 'chain': false }); + * _('fred').vowels(); + * // => ['e'] + */ + function mixin(object, source, options) { + var props = keys(source), + methodNames = baseFunctions(source, props); + + if (options == null && + !(isObject(source) && (methodNames.length || !props.length))) { + options = source; + source = object; + object = this; + methodNames = baseFunctions(source, keys(source)); + } + var chain = !(isObject(options) && 'chain' in options) || !!options.chain, + isFunc = isFunction(object); + + baseEach(methodNames, function(methodName) { + var func = source[methodName]; + object[methodName] = func; + if (isFunc) { + object.prototype[methodName] = function() { + var chainAll = this.__chain__; + if (chain || chainAll) { + var result = object(this.__wrapped__), + actions = result.__actions__ = copyArray(this.__actions__); + + actions.push({ 'func': func, 'args': arguments, 'thisArg': object }); + result.__chain__ = chainAll; + return result; + } + return func.apply(object, arrayPush([this.value()], arguments)); + }; + } + }); + + return object; + } + + /** + * Reverts the `_` variable to its previous value and returns a reference to + * the `lodash` function. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Util + * @returns {Function} Returns the `lodash` function. + * @example + * + * var lodash = _.noConflict(); + */ + function noConflict() { + if (root._ === this) { + root._ = oldDash; + } + return this; + } + + /** + * This method returns `undefined`. + * + * @static + * @memberOf _ + * @since 2.3.0 + * @category Util + * @example + * + * _.times(2, _.noop); + * // => [undefined, undefined] + */ + function noop() { + // No operation performed. + } + + /** + * Generates a unique ID. If `prefix` is given, the ID is appended to it. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Util + * @param {string} [prefix=''] The value to prefix the ID with. + * @returns {string} Returns the unique ID. + * @example + * + * _.uniqueId('contact_'); + * // => 'contact_104' + * + * _.uniqueId(); + * // => '105' + */ + function uniqueId(prefix) { + var id = ++idCounter; + return toString(prefix) + id; + } + + /*------------------------------------------------------------------------*/ + + /** + * Computes the maximum value of `array`. If `array` is empty or falsey, + * `undefined` is returned. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {*} Returns the maximum value. + * @example + * + * _.max([4, 2, 8, 6]); + * // => 8 + * + * _.max([]); + * // => undefined + */ + function max(array) { + return (array && array.length) + ? baseExtremum(array, identity, baseGt) + : undefined; + } + + /** + * Computes the minimum value of `array`. If `array` is empty or falsey, + * `undefined` is returned. + * + * @static + * @since 0.1.0 + * @memberOf _ + * @category Math + * @param {Array} array The array to iterate over. + * @returns {*} Returns the minimum value. + * @example + * + * _.min([4, 2, 8, 6]); + * // => 2 + * + * _.min([]); + * // => undefined + */ + function min(array) { + return (array && array.length) + ? baseExtremum(array, identity, baseLt) + : undefined; + } + + /*------------------------------------------------------------------------*/ + + // Add methods that return wrapped values in chain sequences. + lodash.assignIn = assignIn; + lodash.before = before; + lodash.bind = bind; + lodash.chain = chain; + lodash.compact = compact; + lodash.concat = concat; + lodash.create = create; + lodash.defaults = defaults; + lodash.defer = defer; + lodash.delay = delay; + lodash.filter = filter; + lodash.flatten = flatten; + lodash.flattenDeep = flattenDeep; + lodash.iteratee = iteratee; + lodash.keys = keys; + lodash.map = map; + lodash.matches = matches; + lodash.mixin = mixin; + lodash.negate = negate; + lodash.once = once; + lodash.pick = pick; + lodash.slice = slice; + lodash.sortBy = sortBy; + lodash.tap = tap; + lodash.thru = thru; + lodash.toArray = toArray; + lodash.values = values; + + // Add aliases. + lodash.extend = assignIn; + + // Add methods to `lodash.prototype`. + mixin(lodash, lodash); + + /*------------------------------------------------------------------------*/ + + // Add methods that return unwrapped values in chain sequences. + lodash.clone = clone; + lodash.escape = escape; + lodash.every = every; + lodash.find = find; + lodash.forEach = forEach; + lodash.has = has; + lodash.head = head; + lodash.identity = identity; + lodash.indexOf = indexOf; + lodash.isArguments = isArguments; + lodash.isArray = isArray; + lodash.isBoolean = isBoolean; + lodash.isDate = isDate; + lodash.isEmpty = isEmpty; + lodash.isEqual = isEqual; + lodash.isFinite = isFinite; + lodash.isFunction = isFunction; + lodash.isNaN = isNaN; + lodash.isNull = isNull; + lodash.isNumber = isNumber; + lodash.isObject = isObject; + lodash.isRegExp = isRegExp; + lodash.isString = isString; + lodash.isUndefined = isUndefined; + lodash.last = last; + lodash.max = max; + lodash.min = min; + lodash.noConflict = noConflict; + lodash.noop = noop; + lodash.reduce = reduce; + lodash.result = result; + lodash.size = size; + lodash.some = some; + lodash.uniqueId = uniqueId; + + // Add aliases. + lodash.each = forEach; + lodash.first = head; + + mixin(lodash, (function() { + var source = {}; + baseForOwn(lodash, function(func, methodName) { + if (!hasOwnProperty.call(lodash.prototype, methodName)) { + source[methodName] = func; + } + }); + return source; + }()), { 'chain': false }); + + /*------------------------------------------------------------------------*/ + + /** + * The semantic version number. + * + * @static + * @memberOf _ + * @type {string} + */ + lodash.VERSION = VERSION; + + // Add `Array` methods to `lodash.prototype`. + baseEach(['pop', 'join', 'replace', 'reverse', 'split', 'push', 'shift', 'sort', 'splice', 'unshift'], function(methodName) { + var func = (/^(?:replace|split)$/.test(methodName) ? String.prototype : arrayProto)[methodName], + chainName = /^(?:push|sort|unshift)$/.test(methodName) ? 'tap' : 'thru', + retUnwrapped = /^(?:pop|join|replace|shift)$/.test(methodName); + + lodash.prototype[methodName] = function() { + var args = arguments; + if (retUnwrapped && !this.__chain__) { + var value = this.value(); + return func.apply(isArray(value) ? value : [], args); + } + return this[chainName](function(value) { + return func.apply(isArray(value) ? value : [], args); + }); + }; + }); + + // Add chain sequence methods to the `lodash` wrapper. + lodash.prototype.toJSON = lodash.prototype.valueOf = lodash.prototype.value = wrapperValue; + + /*--------------------------------------------------------------------------*/ + + // Some AMD build optimizers, like r.js, check for condition patterns like: + if (typeof define == 'function' && typeof define.amd == 'object' && define.amd) { + // Expose Lodash on the global object to prevent errors when Lodash is + // loaded by a script tag in the presence of an AMD loader. + // See http://requirejs.org/docs/errors.html#mismatch for more details. + // Use `_.noConflict` to remove Lodash from the global object. + root._ = lodash; + + // Define as an anonymous module so, through path mapping, it can be + // referenced as the "underscore" module. + define(function() { + return lodash; + }); + } + // Check for `exports` after `define` in case a build optimizer adds it. + else if (freeModule) { + // Export for Node.js. + (freeModule.exports = lodash)._ = lodash; + // Export for CommonJS support. + freeExports._ = lodash; + } + else { + // Export to the global object. + root._ = lodash; + } +}.call(this)); |