lodash.custom.js

/**
 * @license
 * lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash exports="node" include="clone,merge,isEmpty,isArray,compact,each" -d`
 * Copyright jQuery Foundation and other contributors <https://jquery.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 = '4.15.0';

  /** Used as the size to enable large array optimizations. */
  var LARGE_ARRAY_SIZE = 200;

  /** Used as the `TypeError` message for "Functions" methods. */
  var FUNC_ERROR_TEXT = 'Expected a function';

  /** Used to stand-in for `undefined` hash values. */
  var HASH_UNDEFINED = '__lodash_hash_undefined__';

  /** Used to compose bitmasks for comparison styles. */
  var UNORDERED_COMPARE_FLAG = 1,
      PARTIAL_COMPARE_FLAG = 2;

  /** 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]',
      boolTag = '[object Boolean]',
      dateTag = '[object Date]',
      errorTag = '[object Error]',
      funcTag = '[object Function]',
      genTag = '[object GeneratorFunction]',
      mapTag = '[object Map]',
      numberTag = '[object Number]',
      objectTag = '[object Object]',
      promiseTag = '[object Promise]',
      regexpTag = '[object RegExp]',
      setTag = '[object Set]',
      stringTag = '[object String]',
      symbolTag = '[object Symbol]',
      weakMapTag = '[object WeakMap]';

  var arrayBufferTag = '[object ArrayBuffer]',
      dataViewTag = '[object DataView]',
      float32Tag = '[object Float32Array]',
      float64Tag = '[object Float64Array]',
      int8Tag = '[object Int8Array]',
      int16Tag = '[object Int16Array]',
      int32Tag = '[object Int32Array]',
      uint8Tag = '[object Uint8Array]',
      uint8ClampedTag = '[object Uint8ClampedArray]',
      uint16Tag = '[object Uint16Array]',
      uint32Tag = '[object Uint32Array]';

  /** Used to match property names within property paths. */
  var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\\]|\\.)*?\1)\]/,
      reIsPlainProp = /^\w*$/,
      reLeadingDot = /^\./,
      rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\\]|\\.)*?)\2)\]|(?=(?:\.|\[\])(?:\.|\[\]|$))/g;

  /**
   * Used to match `RegExp`
   * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns).
   */
  var reRegExpChar = /[\\^$.*+?()[\]{}|]/g;

  /** Used to match backslashes in property paths. */
  var reEscapeChar = /\\(\\)?/g;

  /** Used to match `RegExp` flags from their coerced string values. */
  var reFlags = /\w*$/;

  /** Used to detect host constructors (Safari). */
  var reIsHostCtor = /^\[object .+?Constructor\]$/;

  /** Used to detect unsigned integer values. */
  var reIsUint = /^(?:0|[1-9]\d*)$/;

  /** Used to identify `toStringTag` values of typed arrays. */
  var typedArrayTags = {};
  typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
  typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
  typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
  typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
  typedArrayTags[uint32Tag] = true;
  typedArrayTags[argsTag] = typedArrayTags[arrayTag] =
  typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
  typedArrayTags[dataViewTag] = typedArrayTags[dateTag] =
  typedArrayTags[errorTag] = typedArrayTags[funcTag] =
  typedArrayTags[mapTag] = typedArrayTags[numberTag] =
  typedArrayTags[objectTag] = typedArrayTags[regexpTag] =
  typedArrayTags[setTag] = typedArrayTags[stringTag] =
  typedArrayTags[weakMapTag] = false;

  /** Used to identify `toStringTag` values supported by `_.clone`. */
  var cloneableTags = {};
  cloneableTags[argsTag] = cloneableTags[arrayTag] =
  cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] =
  cloneableTags[boolTag] = cloneableTags[dateTag] =
  cloneableTags[float32Tag] = cloneableTags[float64Tag] =
  cloneableTags[int8Tag] = cloneableTags[int16Tag] =
  cloneableTags[int32Tag] = cloneableTags[mapTag] =
  cloneableTags[numberTag] = cloneableTags[objectTag] =
  cloneableTags[regexpTag] = cloneableTags[setTag] =
  cloneableTags[stringTag] = cloneableTags[symbolTag] =
  cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] =
  cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true;
  cloneableTags[errorTag] = cloneableTags[funcTag] =
  cloneableTags[weakMapTag] = false;

  /** 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;

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

  /** Detect free variable `process` from Node.js. */
  var freeProcess = moduleExports && freeGlobal.process;

  /** Used to access faster Node.js helpers. */
  var nodeUtil = (function() {
    try {
      return freeProcess && freeProcess.binding('util');
    } catch (e) {}
  }());

  /* Node.js helper references. */
  var nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;

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

  /**
   * Adds the key-value `pair` to `map`.
   *
   * @private
   * @param {Object} map The map to modify.
   * @param {Array} pair The key-value pair to add.
   * @returns {Object} Returns `map`.
   */
  function addMapEntry(map, pair) {
    // Don't return `map.set` because it's not chainable in IE 11.
    map.set(pair[0], pair[1]);
    return map;
  }

  /**
   * Adds `value` to `set`.
   *
   * @private
   * @param {Object} set The set to modify.
   * @param {*} value The value to add.
   * @returns {Object} Returns `set`.
   */
  function addSetEntry(set, value) {
    // Don't return `set.add` because it's not chainable in IE 11.
    set.add(value);
    return set;
  }

  /**
   * A faster alternative to `Function#apply`, this function invokes `func`
   * with the `this` binding of `thisArg` and the arguments of `args`.
   *
   * @private
   * @param {Function} func The function to invoke.
   * @param {*} thisArg The `this` binding of `func`.
   * @param {Array} args The arguments to invoke `func` with.
   * @returns {*} Returns the result of `func`.
   */
  function apply(func, thisArg, args) {
    switch (args.length) {
      case 0: return func.call(thisArg);
      case 1: return func.call(thisArg, args[0]);
      case 2: return func.call(thisArg, args[0], args[1]);
      case 3: return func.call(thisArg, args[0], args[1], args[2]);
    }
    return func.apply(thisArg, args);
  }

  /**
   * A specialized version of `_.forEach` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns `array`.
   */
  function arrayEach(array, iteratee) {
    var index = -1,
        length = array ? array.length : 0;

    while (++index < length) {
      if (iteratee(array[index], index, array) === false) {
        break;
      }
    }
    return array;
  }

  /**
   * 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) {
    var index = -1,
        length = values.length,
        offset = array.length;

    while (++index < length) {
      array[offset + index] = values[index];
    }
    return array;
  }

  /**
   * A specialized version of `_.reduce` for arrays without support for
   * iteratee shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} iteratee The function invoked per iteration.
   * @param {*} [accumulator] The initial value.
   * @param {boolean} [initAccum] Specify using the first element of `array` as
   *  the initial value.
   * @returns {*} Returns the accumulated value.
   */
  function arrayReduce(array, iteratee, accumulator, initAccum) {
    var index = -1,
        length = array ? array.length : 0;

    if (initAccum && length) {
      accumulator = array[++index];
    }
    while (++index < length) {
      accumulator = iteratee(accumulator, array[index], index, array);
    }
    return accumulator;
  }

  /**
   * A specialized version of `_.some` for arrays without support for iteratee
   * shorthands.
   *
   * @private
   * @param {Array} [array] The array to iterate over.
   * @param {Function} predicate The function invoked per iteration.
   * @returns {boolean} Returns `true` if any element passes the predicate check,
   *  else `false`.
   */
  function arraySome(array, predicate) {
    var index = -1,
        length = array ? array.length : 0;

    while (++index < length) {
      if (predicate(array[index], index, array)) {
        return true;
      }
    }
    return false;
  }

  /**
   * 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 `_.times` without support for iteratee shorthands
   * or max array length checks.
   *
   * @private
   * @param {number} n The number of times to invoke `iteratee`.
   * @param {Function} iteratee The function invoked per iteration.
   * @returns {Array} Returns the array of results.
   */
  function baseTimes(n, iteratee) {
    var index = -1,
        result = Array(n);

    while (++index < n) {
      result[index] = iteratee(index);
    }
    return result;
  }

  /**
   * The base implementation of `_.unary` without support for storing metadata.
   *
   * @private
   * @param {Function} func The function to cap arguments for.
   * @returns {Function} Returns the new capped function.
   */
  function baseUnary(func) {
    return function(value) {
      return func(value);
    };
  }

  /**
   * Gets the value at `key` of `object`.
   *
   * @private
   * @param {Object} [object] The object to query.
   * @param {string} key The key of the property to get.
   * @returns {*} Returns the property value.
   */
  function getValue(object, key) {
    return object == null ? undefined : object[key];
  }

  /**
   * Checks if `value` is a host object in IE < 9.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a host object, else `false`.
   */
  function isHostObject(value) {
    // Many host objects are `Object` objects that can coerce to strings
    // despite having improperly defined `toString` methods.
    var result = false;
    if (value != null && typeof value.toString != 'function') {
      try {
        result = !!(value + '');
      } catch (e) {}
    }
    return result;
  }

  /**
   * Converts `map` to its key-value pairs.
   *
   * @private
   * @param {Object} map The map to convert.
   * @returns {Array} Returns the key-value pairs.
   */
  function mapToArray(map) {
    var index = -1,
        result = Array(map.size);

    map.forEach(function(value, key) {
      result[++index] = [key, value];
    });
    return result;
  }

  /**
   * 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));
    };
  }

  /**
   * Converts `set` to an array of its values.
   *
   * @private
   * @param {Object} set The set to convert.
   * @returns {Array} Returns the values.
   */
  function setToArray(set) {
    var index = -1,
        result = Array(set.size);

    set.forEach(function(value) {
      result[++index] = value;
    });
    return result;
  }

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

  /** Used for built-in method references. */
  var arrayProto = Array.prototype,
      funcProto = Function.prototype,
      objectProto = Object.prototype;

  /** Used to detect overreaching core-js shims. */
  var coreJsData = root['__core-js_shared__'];

  /** Used to detect methods masquerading as native. */
  var maskSrcKey = (function() {
    var uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || '');
    return uid ? ('Symbol(src)_1.' + uid) : '';
  }());

  /** Used to resolve the decompiled source of functions. */
  var funcToString = funcProto.toString;

  /** Used to check objects for own properties. */
  var hasOwnProperty = objectProto.hasOwnProperty;

  /** Used to infer the `Object` constructor. */
  var objectCtorString = funcToString.call(Object);

  /**
   * Used to resolve the
   * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
   * of values.
   */
  var objectToString = objectProto.toString;

  /** Used to detect if a method is native. */
  var reIsNative = RegExp('^' +
    funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&')
    .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
  );

  /** Built-in value references. */
  var Buffer = moduleExports ? root.Buffer : undefined,
      Symbol = root.Symbol,
      Uint8Array = root.Uint8Array,
      getPrototype = overArg(Object.getPrototypeOf, Object),
      objectCreate = Object.create,
      propertyIsEnumerable = objectProto.propertyIsEnumerable,
      splice = arrayProto.splice;

  /* Built-in method references for those with the same name as other `lodash` methods. */
  var nativeGetSymbols = Object.getOwnPropertySymbols,
      nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined,
      nativeKeys = overArg(Object.keys, Object),
      nativeMax = Math.max;

  /* Built-in method references that are verified to be native. */
  var DataView = getNative(root, 'DataView'),
      Map = getNative(root, 'Map'),
      Promise = getNative(root, 'Promise'),
      Set = getNative(root, 'Set'),
      WeakMap = getNative(root, 'WeakMap'),
      nativeCreate = getNative(Object, 'create');

  /** Detect if properties shadowing those on `Object.prototype` are non-enumerable. */
  var nonEnumShadows = !propertyIsEnumerable.call({ 'valueOf': 1 }, 'valueOf');

  /** Used to lookup unminified function names. */
  var realNames = {};

  /** Used to detect maps, sets, and weakmaps. */
  var dataViewCtorString = toSource(DataView),
      mapCtorString = toSource(Map),
      promiseCtorString = toSource(Promise),
      setCtorString = toSource(Set),
      weakMapCtorString = toSource(WeakMap);

  /** Used to convert symbols to primitives and strings. */
  var symbolProto = Symbol ? Symbol.prototype : undefined,
      symbolValueOf = symbolProto ? symbolProto.valueOf : undefined,
      symbolToString = symbolProto ? symbolProto.toString : undefined;

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

  /**
   * 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 of at least `200` elements
   * and any 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() {
    // No operation performed.
  }

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

  /**
   * Creates a hash object.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function Hash(entries) {
    var index = -1,
        length = entries ? entries.length : 0;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the hash.
   *
   * @private
   * @name clear
   * @memberOf Hash
   */
  function hashClear() {
    this.__data__ = nativeCreate ? nativeCreate(null) : {};
  }

  /**
   * Removes `key` and its value from the hash.
   *
   * @private
   * @name delete
   * @memberOf Hash
   * @param {Object} hash The hash to modify.
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function hashDelete(key) {
    return this.has(key) && delete this.__data__[key];
  }

  /**
   * Gets the hash value for `key`.
   *
   * @private
   * @name get
   * @memberOf Hash
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function hashGet(key) {
    var data = this.__data__;
    if (nativeCreate) {
      var result = data[key];
      return result === HASH_UNDEFINED ? undefined : result;
    }
    return hasOwnProperty.call(data, key) ? data[key] : undefined;
  }

  /**
   * Checks if a hash value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf Hash
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function hashHas(key) {
    var data = this.__data__;
    return nativeCreate ? data[key] !== undefined : hasOwnProperty.call(data, key);
  }

  /**
   * Sets the hash `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf Hash
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the hash instance.
   */
  function hashSet(key, value) {
    var data = this.__data__;
    data[key] = (nativeCreate && value === undefined) ? HASH_UNDEFINED : value;
    return this;
  }

  // Add methods to `Hash`.
  Hash.prototype.clear = hashClear;
  Hash.prototype['delete'] = hashDelete;
  Hash.prototype.get = hashGet;
  Hash.prototype.has = hashHas;
  Hash.prototype.set = hashSet;

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

  /**
   * Creates an list cache object.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function ListCache(entries) {
    var index = -1,
        length = entries ? entries.length : 0;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the list cache.
   *
   * @private
   * @name clear
   * @memberOf ListCache
   */
  function listCacheClear() {
    this.__data__ = [];
  }

  /**
   * Removes `key` and its value from the list cache.
   *
   * @private
   * @name delete
   * @memberOf ListCache
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function listCacheDelete(key) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    if (index < 0) {
      return false;
    }
    var lastIndex = data.length - 1;
    if (index == lastIndex) {
      data.pop();
    } else {
      splice.call(data, index, 1);
    }
    return true;
  }

  /**
   * Gets the list cache value for `key`.
   *
   * @private
   * @name get
   * @memberOf ListCache
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function listCacheGet(key) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    return index < 0 ? undefined : data[index][1];
  }

  /**
   * Checks if a list cache value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf ListCache
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function listCacheHas(key) {
    return assocIndexOf(this.__data__, key) > -1;
  }

  /**
   * Sets the list cache `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf ListCache
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the list cache instance.
   */
  function listCacheSet(key, value) {
    var data = this.__data__,
        index = assocIndexOf(data, key);

    if (index < 0) {
      data.push([key, value]);
    } else {
      data[index][1] = value;
    }
    return this;
  }

  // Add methods to `ListCache`.
  ListCache.prototype.clear = listCacheClear;
  ListCache.prototype['delete'] = listCacheDelete;
  ListCache.prototype.get = listCacheGet;
  ListCache.prototype.has = listCacheHas;
  ListCache.prototype.set = listCacheSet;

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

  /**
   * Creates a map cache object to store key-value pairs.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function MapCache(entries) {
    var index = -1,
        length = entries ? entries.length : 0;

    this.clear();
    while (++index < length) {
      var entry = entries[index];
      this.set(entry[0], entry[1]);
    }
  }

  /**
   * Removes all key-value entries from the map.
   *
   * @private
   * @name clear
   * @memberOf MapCache
   */
  function mapCacheClear() {
    this.__data__ = {
      'hash': new Hash,
      'map': new (Map || ListCache),
      'string': new Hash
    };
  }

  /**
   * Removes `key` and its value from the map.
   *
   * @private
   * @name delete
   * @memberOf MapCache
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function mapCacheDelete(key) {
    return getMapData(this, key)['delete'](key);
  }

  /**
   * Gets the map value for `key`.
   *
   * @private
   * @name get
   * @memberOf MapCache
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function mapCacheGet(key) {
    return getMapData(this, key).get(key);
  }

  /**
   * Checks if a map value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf MapCache
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function mapCacheHas(key) {
    return getMapData(this, key).has(key);
  }

  /**
   * Sets the map `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf MapCache
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the map cache instance.
   */
  function mapCacheSet(key, value) {
    getMapData(this, key).set(key, value);
    return this;
  }

  // Add methods to `MapCache`.
  MapCache.prototype.clear = mapCacheClear;
  MapCache.prototype['delete'] = mapCacheDelete;
  MapCache.prototype.get = mapCacheGet;
  MapCache.prototype.has = mapCacheHas;
  MapCache.prototype.set = mapCacheSet;

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

  /**
   *
   * Creates an array cache object to store unique values.
   *
   * @private
   * @constructor
   * @param {Array} [values] The values to cache.
   */
  function SetCache(values) {
    var index = -1,
        length = values ? values.length : 0;

    this.__data__ = new MapCache;
    while (++index < length) {
      this.add(values[index]);
    }
  }

  /**
   * Adds `value` to the array cache.
   *
   * @private
   * @name add
   * @memberOf SetCache
   * @alias push
   * @param {*} value The value to cache.
   * @returns {Object} Returns the cache instance.
   */
  function setCacheAdd(value) {
    this.__data__.set(value, HASH_UNDEFINED);
    return this;
  }

  /**
   * Checks if `value` is in the array cache.
   *
   * @private
   * @name has
   * @memberOf SetCache
   * @param {*} value The value to search for.
   * @returns {number} Returns `true` if `value` is found, else `false`.
   */
  function setCacheHas(value) {
    return this.__data__.has(value);
  }

  // Add methods to `SetCache`.
  SetCache.prototype.add = SetCache.prototype.push = setCacheAdd;
  SetCache.prototype.has = setCacheHas;

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

  /**
   * Creates a stack cache object to store key-value pairs.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function Stack(entries) {
    this.__data__ = new ListCache(entries);
  }

  /**
   * Removes all key-value entries from the stack.
   *
   * @private
   * @name clear
   * @memberOf Stack
   */
  function stackClear() {
    this.__data__ = new ListCache;
  }

  /**
   * Removes `key` and its value from the stack.
   *
   * @private
   * @name delete
   * @memberOf Stack
   * @param {string} key The key of the value to remove.
   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
   */
  function stackDelete(key) {
    return this.__data__['delete'](key);
  }

  /**
   * Gets the stack value for `key`.
   *
   * @private
   * @name get
   * @memberOf Stack
   * @param {string} key The key of the value to get.
   * @returns {*} Returns the entry value.
   */
  function stackGet(key) {
    return this.__data__.get(key);
  }

  /**
   * Checks if a stack value for `key` exists.
   *
   * @private
   * @name has
   * @memberOf Stack
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function stackHas(key) {
    return this.__data__.has(key);
  }

  /**
   * Sets the stack `key` to `value`.
   *
   * @private
   * @name set
   * @memberOf Stack
   * @param {string} key The key of the value to set.
   * @param {*} value The value to set.
   * @returns {Object} Returns the stack cache instance.
   */
  function stackSet(key, value) {
    var cache = this.__data__;
    if (cache instanceof ListCache) {
      var pairs = cache.__data__;
      if (!Map || (pairs.length < LARGE_ARRAY_SIZE - 1)) {
        pairs.push([key, value]);
        return this;
      }
      cache = this.__data__ = new MapCache(pairs);
    }
    cache.set(key, value);
    return this;
  }

  // Add methods to `Stack`.
  Stack.prototype.clear = stackClear;
  Stack.prototype['delete'] = stackDelete;
  Stack.prototype.get = stackGet;
  Stack.prototype.has = stackHas;
  Stack.prototype.set = stackSet;

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

  /**
   * Creates an array of the enumerable property names of the array-like `value`.
   *
   * @private
   * @param {*} value The value to query.
   * @param {boolean} inherited Specify returning inherited property names.
   * @returns {Array} Returns the array of property names.
   */
  function arrayLikeKeys(value, inherited) {
    // Safari 8.1 makes `arguments.callee` enumerable in strict mode.
    // Safari 9 makes `arguments.length` enumerable in strict mode.
    var result = (isArray(value) || isArguments(value))
      ? baseTimes(value.length, String)
      : [];

    var length = result.length,
        skipIndexes = !!length;

    for (var key in value) {
      if ((inherited || hasOwnProperty.call(value, key)) &&
          !(skipIndexes && (key == 'length' || isIndex(key, length)))) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * This function is like `assignValue` except that it doesn't assign
   * `undefined` values.
   *
   * @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 assignMergeValue(object, key, value) {
    if ((value !== undefined && !eq(object[key], value)) ||
        (typeof key == 'number' && value === undefined && !(key in object))) {
      object[key] = value;
    }
  }

  /**
   * 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))) {
      object[key] = value;
    }
  }

  /**
   * Gets the index at which the `key` is found in `array` of key-value pairs.
   *
   * @private
   * @param {Array} array The array to inspect.
   * @param {*} key The key to search for.
   * @returns {number} Returns the index of the matched value, else `-1`.
   */
  function assocIndexOf(array, key) {
    var length = array.length;
    while (length--) {
      if (eq(array[length][0], key)) {
        return length;
      }
    }
    return -1;
  }

  /**
   * The base implementation of `_.assign` without support for multiple sources
   * or `customizer` functions.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @returns {Object} Returns `object`.
   */
  function baseAssign(object, source) {
    return object && copyObject(source, keys(source), object);
  }

  /**
   * The base implementation of `_.clone` and `_.cloneDeep` which tracks
   * traversed objects.
   *
   * @private
   * @param {*} value The value to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @param {boolean} [isFull] Specify a clone including symbols.
   * @param {Function} [customizer] The function to customize cloning.
   * @param {string} [key] The key of `value`.
   * @param {Object} [object] The parent object of `value`.
   * @param {Object} [stack] Tracks traversed objects and their clone counterparts.
   * @returns {*} Returns the cloned value.
   */
  function baseClone(value, isDeep, isFull, customizer, key, object, stack) {
    var result;
    if (customizer) {
      result = object ? customizer(value, key, object, stack) : customizer(value);
    }
    if (result !== undefined) {
      return result;
    }
    if (!isObject(value)) {
      return value;
    }
    var isArr = isArray(value);
    if (isArr) {
      result = initCloneArray(value);
      if (!isDeep) {
        return copyArray(value, result);
      }
    } else {
      var tag = getTag(value),
          isFunc = tag == funcTag || tag == genTag;

      if (isBuffer(value)) {
        return cloneBuffer(value, isDeep);
      }
      if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
        if (isHostObject(value)) {
          return object ? value : {};
        }
        result = initCloneObject(isFunc ? {} : value);
        if (!isDeep) {
          return copySymbols(value, baseAssign(result, value));
        }
      } else {
        if (!cloneableTags[tag]) {
          return object ? value : {};
        }
        result = initCloneByTag(value, tag, baseClone, isDeep);
      }
    }
    // Check for circular references and return its corresponding clone.
    stack || (stack = new Stack);
    var stacked = stack.get(value);
    if (stacked) {
      return stacked;
    }
    stack.set(value, result);

    if (!isArr) {
      var props = isFull ? getAllKeys(value) : keys(value);
    }
    arrayEach(props || value, function(subValue, key) {
      if (props) {
        key = subValue;
        subValue = value[key];
      }
      // Recursively populate clone (susceptible to call stack limits).
      assignValue(result, key, baseClone(subValue, isDeep, isFull, customizer, key, value, stack));
    });
    return result;
  }

  /**
   * The base implementation of `_.create` without support for assigning
   * properties to the created object.
   *
   * @private
   * @param {Object} prototype The object to inherit from.
   * @returns {Object} Returns the new object.
   */
  function baseCreate(proto) {
    return isObject(proto) ? objectCreate(proto) : {};
  }

  /**
   * 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 `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 `_.get` without support for default values.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the property to get.
   * @returns {*} Returns the resolved value.
   */
  function baseGet(object, path) {
    path = isKey(path, object) ? [path] : castPath(path);

    var index = 0,
        length = path.length;

    while (object != null && index < length) {
      object = object[toKey(path[index++])];
    }
    return (index && index == length) ? object : undefined;
  }

  /**
   * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
   * `keysFunc` and `symbolsFunc` to get the enumerable property names and
   * symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Function} keysFunc The function to get the keys of `object`.
   * @param {Function} symbolsFunc The function to get the symbols of `object`.
   * @returns {Array} Returns the array of property names and symbols.
   */
  function baseGetAllKeys(object, keysFunc, symbolsFunc) {
    var result = keysFunc(object);
    return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
  }

  /**
   * The base implementation of `getTag`.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the `toStringTag`.
   */
  function baseGetTag(value) {
    return objectToString.call(value);
  }

  /**
   * The base implementation of `_.hasIn` without support for deep paths.
   *
   * @private
   * @param {Object} [object] The object to query.
   * @param {Array|string} key The key to check.
   * @returns {boolean} Returns `true` if `key` exists, else `false`.
   */
  function baseHasIn(object, key) {
    return object != null && key in Object(object);
  }

  /**
   * 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 {Function} [customizer] The function to customize comparisons.
   * @param {boolean} [bitmask] The bitmask of comparison flags.
   *  The bitmask may be composed of the following flags:
   *     1 - Unordered comparison
   *     2 - Partial comparison
   * @param {Object} [stack] Tracks traversed `value` and `other` objects.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   */
  function baseIsEqual(value, other, customizer, bitmask, stack) {
    if (value === other) {
      return true;
    }
    if (value == null || other == null || (!isObject(value) && !isObjectLike(other))) {
      return value !== value && other !== other;
    }
    return baseIsEqualDeep(value, other, baseIsEqual, customizer, bitmask, 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 {Function} equalFunc The function to determine equivalents of values.
   * @param {Function} [customizer] The function to customize comparisons.
   * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual`
   *  for more details.
   * @param {Object} [stack] Tracks traversed `object` and `other` objects.
   * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
   */
  function baseIsEqualDeep(object, other, equalFunc, customizer, bitmask, stack) {
    var objIsArr = isArray(object),
        othIsArr = isArray(other),
        objTag = arrayTag,
        othTag = arrayTag;

    if (!objIsArr) {
      objTag = getTag(object);
      objTag = objTag == argsTag ? objectTag : objTag;
    }
    if (!othIsArr) {
      othTag = getTag(other);
      othTag = othTag == argsTag ? objectTag : othTag;
    }
    var objIsObj = objTag == objectTag && !isHostObject(object),
        othIsObj = othTag == objectTag && !isHostObject(other),
        isSameTag = objTag == othTag;

    if (isSameTag && !objIsObj) {
      stack || (stack = new Stack);
      return (objIsArr || isTypedArray(object))
        ? equalArrays(object, other, equalFunc, customizer, bitmask, stack)
        : equalByTag(object, other, objTag, equalFunc, customizer, bitmask, stack);
    }
    if (!(bitmask & PARTIAL_COMPARE_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;

        stack || (stack = new Stack);
        return equalFunc(objUnwrapped, othUnwrapped, customizer, bitmask, stack);
      }
    }
    if (!isSameTag) {
      return false;
    }
    stack || (stack = new Stack);
    return equalObjects(object, other, equalFunc, customizer, bitmask, stack);
  }

  /**
   * The base implementation of `_.isMatch` without support for iteratee shorthands.
   *
   * @private
   * @param {Object} object The object to inspect.
   * @param {Object} source The object of property values to match.
   * @param {Array} matchData The property names, values, and compare flags to match.
   * @param {Function} [customizer] The function to customize comparisons.
   * @returns {boolean} Returns `true` if `object` is a match, else `false`.
   */
  function baseIsMatch(object, source, matchData, customizer) {
    var index = matchData.length,
        length = index,
        noCustomizer = !customizer;

    if (object == null) {
      return !length;
    }
    object = Object(object);
    while (index--) {
      var data = matchData[index];
      if ((noCustomizer && data[2])
            ? data[1] !== object[data[0]]
            : !(data[0] in object)
          ) {
        return false;
      }
    }
    while (++index < length) {
      data = matchData[index];
      var key = data[0],
          objValue = object[key],
          srcValue = data[1];

      if (noCustomizer && data[2]) {
        if (objValue === undefined && !(key in object)) {
          return false;
        }
      } else {
        var stack = new Stack;
        if (customizer) {
          var result = customizer(objValue, srcValue, key, object, source, stack);
        }
        if (!(result === undefined
              ? baseIsEqual(srcValue, objValue, customizer, UNORDERED_COMPARE_FLAG | PARTIAL_COMPARE_FLAG, stack)
              : result
            )) {
          return false;
        }
      }
    }
    return true;
  }

  /**
   * The base implementation of `_.isNative` without bad shim checks.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a native function,
   *  else `false`.
   */
  function baseIsNative(value) {
    if (!isObject(value) || isMasked(value)) {
      return false;
    }
    var pattern = (isFunction(value) || isHostObject(value)) ? reIsNative : reIsHostCtor;
    return pattern.test(toSource(value));
  }

  /**
   * The base implementation of `_.isTypedArray` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
   */
  function baseIsTypedArray(value) {
    return isObjectLike(value) &&
      isLength(value.length) && !!typedArrayTags[objectToString.call(value)];
  }

  /**
   * The base implementation of `_.iteratee`.
   *
   * @private
   * @param {*} [value=_.identity] The value to convert to an iteratee.
   * @returns {Function} Returns the iteratee.
   */
  function baseIteratee(value) {
    // Don't store the `typeof` result in a variable to avoid a JIT bug in Safari 9.
    // See https://bugs.webkit.org/show_bug.cgi?id=156034 for more details.
    if (typeof value == 'function') {
      return value;
    }
    if (value == null) {
      return identity;
    }
    if (typeof value == 'object') {
      return isArray(value)
        ? baseMatchesProperty(value[0], value[1])
        : baseMatches(value);
    }
    return property(value);
  }

  /**
   * The base implementation of `_.keys` which doesn't treat sparse arrays as dense.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function baseKeys(object) {
    if (!isPrototype(object)) {
      return nativeKeys(object);
    }
    var result = [];
    for (var key in Object(object)) {
      if (hasOwnProperty.call(object, key) && key != 'constructor') {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function baseKeysIn(object) {
    if (!isObject(object)) {
      return nativeKeysIn(object);
    }
    var isProto = isPrototype(object),
        result = [];

    for (var key in object) {
      if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
        result.push(key);
      }
    }
    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 matchData = getMatchData(source);
    if (matchData.length == 1 && matchData[0][2]) {
      return matchesStrictComparable(matchData[0][0], matchData[0][1]);
    }
    return function(object) {
      return object === source || baseIsMatch(object, source, matchData);
    };
  }

  /**
   * The base implementation of `_.matchesProperty` which doesn't clone `srcValue`.
   *
   * @private
   * @param {string} path The path of the property to get.
   * @param {*} srcValue The value to match.
   * @returns {Function} Returns the new spec function.
   */
  function baseMatchesProperty(path, srcValue) {
    if (isKey(path) && isStrictComparable(srcValue)) {
      return matchesStrictComparable(toKey(path), srcValue);
    }
    return function(object) {
      var objValue = get(object, path);
      return (objValue === undefined && objValue === srcValue)
        ? hasIn(object, path)
        : baseIsEqual(srcValue, objValue, undefined, UNORDERED_COMPARE_FLAG | PARTIAL_COMPARE_FLAG);
    };
  }

  /**
   * The base implementation of `_.merge` without support for multiple sources.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @param {number} srcIndex The index of `source`.
   * @param {Function} [customizer] The function to customize merged values.
   * @param {Object} [stack] Tracks traversed source values and their merged
   *  counterparts.
   */
  function baseMerge(object, source, srcIndex, customizer, stack) {
    if (object === source) {
      return;
    }
    if (!(isArray(source) || isTypedArray(source))) {
      var props = baseKeysIn(source);
    }
    arrayEach(props || source, function(srcValue, key) {
      if (props) {
        key = srcValue;
        srcValue = source[key];
      }
      if (isObject(srcValue)) {
        stack || (stack = new Stack);
        baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack);
      }
      else {
        var newValue = customizer
          ? customizer(object[key], srcValue, (key + ''), object, source, stack)
          : undefined;

        if (newValue === undefined) {
          newValue = srcValue;
        }
        assignMergeValue(object, key, newValue);
      }
    });
  }

  /**
   * A specialized version of `baseMerge` for arrays and objects which performs
   * deep merges and tracks traversed objects enabling objects with circular
   * references to be merged.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @param {string} key The key of the value to merge.
   * @param {number} srcIndex The index of `source`.
   * @param {Function} mergeFunc The function to merge values.
   * @param {Function} [customizer] The function to customize assigned values.
   * @param {Object} [stack] Tracks traversed source values and their merged
   *  counterparts.
   */
  function baseMergeDeep(object, source, key, srcIndex, mergeFunc, customizer, stack) {
    var objValue = object[key],
        srcValue = source[key],
        stacked = stack.get(srcValue);

    if (stacked) {
      assignMergeValue(object, key, stacked);
      return;
    }
    var newValue = customizer
      ? customizer(objValue, srcValue, (key + ''), object, source, stack)
      : undefined;

    var isCommon = newValue === undefined;

    if (isCommon) {
      newValue = srcValue;
      if (isArray(srcValue) || isTypedArray(srcValue)) {
        if (isArray(objValue)) {
          newValue = objValue;
        }
        else if (isArrayLikeObject(objValue)) {
          newValue = copyArray(objValue);
        }
        else {
          isCommon = false;
          newValue = baseClone(srcValue, true);
        }
      }
      else if (isPlainObject(srcValue) || isArguments(srcValue)) {
        if (isArguments(objValue)) {
          newValue = toPlainObject(objValue);
        }
        else if (!isObject(objValue) || (srcIndex && isFunction(objValue))) {
          isCommon = false;
          newValue = baseClone(srcValue, true);
        }
        else {
          newValue = objValue;
        }
      }
      else {
        isCommon = false;
      }
    }
    if (isCommon) {
      // Recursively merge objects and arrays (susceptible to call stack limits).
      stack.set(srcValue, newValue);
      mergeFunc(newValue, srcValue, srcIndex, customizer, stack);
      stack['delete'](srcValue);
    }
    assignMergeValue(object, key, newValue);
  }

  /**
   * A specialized version of `baseProperty` which supports deep paths.
   *
   * @private
   * @param {Array|string} path The path of the property to get.
   * @returns {Function} Returns the new accessor function.
   */
  function basePropertyDeep(path) {
    return function(object) {
      return baseGet(object, path);
    };
  }

  /**
   * 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) {
    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] = array;
      return apply(func, this, otherArgs);
    };
  }

  /**
   * The base implementation of `_.toString` which doesn't convert nullish
   * values to empty strings.
   *
   * @private
   * @param {*} value The value to process.
   * @returns {string} Returns the string.
   */
  function baseToString(value) {
    // Exit early for strings to avoid a performance hit in some environments.
    if (typeof value == 'string') {
      return value;
    }
    if (isSymbol(value)) {
      return symbolToString ? symbolToString.call(value) : '';
    }
    var result = (value + '');
    return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
  }

  /**
   * Casts `value` to a path array if it's not one.
   *
   * @private
   * @param {*} value The value to inspect.
   * @returns {Array} Returns the cast property path array.
   */
  function castPath(value) {
    return isArray(value) ? value : stringToPath(value);
  }

  /**
   * Creates a clone of  `buffer`.
   *
   * @private
   * @param {Buffer} buffer The buffer to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Buffer} Returns the cloned buffer.
   */
  function cloneBuffer(buffer, isDeep) {
    if (isDeep) {
      return buffer.slice();
    }
    var result = new buffer.constructor(buffer.length);
    buffer.copy(result);
    return result;
  }

  /**
   * Creates a clone of `arrayBuffer`.
   *
   * @private
   * @param {ArrayBuffer} arrayBuffer The array buffer to clone.
   * @returns {ArrayBuffer} Returns the cloned array buffer.
   */
  function cloneArrayBuffer(arrayBuffer) {
    var result = new arrayBuffer.constructor(arrayBuffer.byteLength);
    new Uint8Array(result).set(new Uint8Array(arrayBuffer));
    return result;
  }

  /**
   * Creates a clone of `dataView`.
   *
   * @private
   * @param {Object} dataView The data view to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned data view.
   */
  function cloneDataView(dataView, isDeep) {
    var buffer = isDeep ? cloneArrayBuffer(dataView.buffer) : dataView.buffer;
    return new dataView.constructor(buffer, dataView.byteOffset, dataView.byteLength);
  }

  /**
   * Creates a clone of `map`.
   *
   * @private
   * @param {Object} map The map to clone.
   * @param {Function} cloneFunc The function to clone values.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned map.
   */
  function cloneMap(map, isDeep, cloneFunc) {
    var array = isDeep ? cloneFunc(mapToArray(map), true) : mapToArray(map);
    return arrayReduce(array, addMapEntry, new map.constructor);
  }

  /**
   * Creates a clone of `regexp`.
   *
   * @private
   * @param {Object} regexp The regexp to clone.
   * @returns {Object} Returns the cloned regexp.
   */
  function cloneRegExp(regexp) {
    var result = new regexp.constructor(regexp.source, reFlags.exec(regexp));
    result.lastIndex = regexp.lastIndex;
    return result;
  }

  /**
   * Creates a clone of `set`.
   *
   * @private
   * @param {Object} set The set to clone.
   * @param {Function} cloneFunc The function to clone values.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned set.
   */
  function cloneSet(set, isDeep, cloneFunc) {
    var array = isDeep ? cloneFunc(setToArray(set), true) : setToArray(set);
    return arrayReduce(array, addSetEntry, new set.constructor);
  }

  /**
   * Creates a clone of the `symbol` object.
   *
   * @private
   * @param {Object} symbol The symbol object to clone.
   * @returns {Object} Returns the cloned symbol object.
   */
  function cloneSymbol(symbol) {
    return symbolValueOf ? Object(symbolValueOf.call(symbol)) : {};
  }

  /**
   * Creates a clone of `typedArray`.
   *
   * @private
   * @param {Object} typedArray The typed array to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the cloned typed array.
   */
  function cloneTypedArray(typedArray, isDeep) {
    var buffer = isDeep ? cloneArrayBuffer(typedArray.buffer) : typedArray.buffer;
    return new typedArray.constructor(buffer, typedArray.byteOffset, typedArray.length);
  }

  /**
   * 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, array) {
    var index = -1,
        length = source.length;

    array || (array = Array(length));
    while (++index < length) {
      array[index] = source[index];
    }
    return array;
  }

  /**
   * 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) {
    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;

      assignValue(object, key, newValue === undefined ? source[key] : newValue);
    }
    return object;
  }

  /**
   * Copies own symbol properties of `source` to `object`.
   *
   * @private
   * @param {Object} source The object to copy symbols from.
   * @param {Object} [object={}] The object to copy symbols to.
   * @returns {Object} Returns `object`.
   */
  function copySymbols(source, object) {
    return copyObject(source, getSymbols(source), 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,
          guard = length > 2 ? sources[2] : undefined;

      customizer = (assigner.length > 3 && typeof customizer == 'function')
        ? (length--, customizer)
        : undefined;

      if (guard && isIterateeCall(sources[0], sources[1], guard)) {
        customizer = length < 3 ? undefined : customizer;
        length = 1;
      }
      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;
    };
  }

  /**
   * 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 {Function} equalFunc The function to determine equivalents of values.
   * @param {Function} customizer The function to customize comparisons.
   * @param {number} bitmask The bitmask of comparison flags. See `baseIsEqual`
   *  for more details.
   * @param {Object} stack Tracks traversed `array` and `other` objects.
   * @returns {boolean} Returns `true` if the arrays are equivalent, else `false`.
   */
  function equalArrays(array, other, equalFunc, customizer, bitmask, stack) {
    var isPartial = bitmask & PARTIAL_COMPARE_FLAG,
        arrLength = array.length,
        othLength = other.length;

    if (arrLength != othLength && !(isPartial && othLength > arrLength)) {
      return false;
    }
    // Assume cyclic values are equal.
    var stacked = stack.get(array);
    if (stacked && stack.get(other)) {
      return stacked == other;
    }
    var index = -1,
        result = true,
        seen = (bitmask & UNORDERED_COMPARE_FLAG) ? new SetCache : undefined;

    stack.set(array, other);
    stack.set(other, array);

    // Ignore non-index properties.
    while (++index < arrLength) {
      var arrValue = array[index],
          othValue = other[index];

      if (customizer) {
        var compared = isPartial
          ? customizer(othValue, arrValue, index, other, array, stack)
          : customizer(arrValue, othValue, index, array, other, stack);
      }
      if (compared !== undefined) {
        if (compared) {
          continue;
        }
        result = false;
        break;
      }
      // Recursively compare arrays (susceptible to call stack limits).
      if (seen) {
        if (!arraySome(other, function(othValue, othIndex) {
              if (!seen.has(othIndex) &&
                  (arrValue === othValue || equalFunc(arrValue, othValue, customizer, bitmask, stack))) {
                return seen.add(othIndex);
              }
            })) {
          result = false;
          break;
        }
      } else if (!(
            arrValue === othValue ||
              equalFunc(arrValue, othValue, customizer, bitmask, stack)
          )) {
        result = false;
        break;
      }
    }
    stack['delete'](array);
    stack['delete'](other);
    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 {Function} equalFunc The function to determine equivalents of values.
   * @param {Function} customizer The function to customize comparisons.
   * @param {number} bitmask The bitmask of comparison flags. See `baseIsEqual`
   *  for more details.
   * @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, equalFunc, customizer, bitmask, stack) {
    switch (tag) {
      case dataViewTag:
        if ((object.byteLength != other.byteLength) ||
            (object.byteOffset != other.byteOffset)) {
          return false;
        }
        object = object.buffer;
        other = other.buffer;

      case arrayBufferTag:
        if ((object.byteLength != other.byteLength) ||
            !equalFunc(new Uint8Array(object), new Uint8Array(other))) {
          return false;
        }
        return true;

      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 + '');

      case mapTag:
        var convert = mapToArray;

      case setTag:
        var isPartial = bitmask & PARTIAL_COMPARE_FLAG;
        convert || (convert = setToArray);

        if (object.size != other.size && !isPartial) {
          return false;
        }
        // Assume cyclic values are equal.
        var stacked = stack.get(object);
        if (stacked) {
          return stacked == other;
        }
        bitmask |= UNORDERED_COMPARE_FLAG;

        // Recursively compare objects (susceptible to call stack limits).
        stack.set(object, other);
        var result = equalArrays(convert(object), convert(other), equalFunc, customizer, bitmask, stack);
        stack['delete'](object);
        return result;

      case symbolTag:
        if (symbolValueOf) {
          return symbolValueOf.call(object) == symbolValueOf.call(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 {Function} equalFunc The function to determine equivalents of values.
   * @param {Function} customizer The function to customize comparisons.
   * @param {number} bitmask The bitmask of comparison flags. See `baseIsEqual`
   *  for more details.
   * @param {Object} stack Tracks traversed `object` and `other` objects.
   * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
   */
  function equalObjects(object, other, equalFunc, customizer, bitmask, stack) {
    var isPartial = bitmask & PARTIAL_COMPARE_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;
      }
    }
    // Assume cyclic values are equal.
    var stacked = stack.get(object);
    if (stacked && stack.get(other)) {
      return stacked == other;
    }
    var result = true;
    stack.set(object, other);
    stack.set(other, object);

    var skipCtor = isPartial;
    while (++index < objLength) {
      key = objProps[index];
      var objValue = object[key],
          othValue = other[key];

      if (customizer) {
        var compared = isPartial
          ? customizer(othValue, objValue, key, other, object, stack)
          : customizer(objValue, othValue, key, object, other, stack);
      }
      // Recursively compare objects (susceptible to call stack limits).
      if (!(compared === undefined
            ? (objValue === othValue || equalFunc(objValue, othValue, customizer, bitmask, 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;
      }
    }
    stack['delete'](object);
    stack['delete'](other);
    return result;
  }

  /**
   * Creates an array of own enumerable property names and symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names and symbols.
   */
  function getAllKeys(object) {
    return baseGetAllKeys(object, keys, getSymbols);
  }

  /**
   * Gets the appropriate "iteratee" function. If `_.iteratee` is customized,
   * this function returns the custom method, otherwise it returns `baseIteratee`.
   * If arguments are provided, the chosen function is invoked with them and
   * its result is returned.
   *
   * @private
   * @param {*} [value] The value to convert to an iteratee.
   * @param {number} [arity] The arity of the created iteratee.
   * @returns {Function} Returns the chosen function or its result.
   */
  function getIteratee() {
    var result = lodash.iteratee || iteratee;
    result = result === iteratee ? baseIteratee : result;
    return arguments.length ? result(arguments[0], arguments[1]) : result;
  }

  /**
   * Gets the data for `map`.
   *
   * @private
   * @param {Object} map The map to query.
   * @param {string} key The reference key.
   * @returns {*} Returns the map data.
   */
  function getMapData(map, key) {
    var data = map.__data__;
    return isKeyable(key)
      ? data[typeof key == 'string' ? 'string' : 'hash']
      : data.map;
  }

  /**
   * Gets the property names, values, and compare flags of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the match data of `object`.
   */
  function getMatchData(object) {
    var result = keys(object),
        length = result.length;

    while (length--) {
      var key = result[length],
          value = object[key];

      result[length] = [key, value, isStrictComparable(value)];
    }
    return result;
  }

  /**
   * Gets the native function at `key` of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {string} key The key of the method to get.
   * @returns {*} Returns the function if it's native, else `undefined`.
   */
  function getNative(object, key) {
    var value = getValue(object, key);
    return baseIsNative(value) ? value : undefined;
  }

  /**
   * Creates an array of the own enumerable symbol properties of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of symbols.
   */
  var getSymbols = nativeGetSymbols ? overArg(nativeGetSymbols, Object) : stubArray;

  /**
   * Gets the `toStringTag` of `value`.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the `toStringTag`.
   */
  var getTag = baseGetTag;

  // Fallback for data views, maps, sets, and weak maps in IE 11,
  // for data views in Edge < 14, and promises in Node.js.
  if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) ||
      (Map && getTag(new Map) != mapTag) ||
      (Promise && getTag(Promise.resolve()) != promiseTag) ||
      (Set && getTag(new Set) != setTag) ||
      (WeakMap && getTag(new WeakMap) != weakMapTag)) {
    getTag = function(value) {
      var result = objectToString.call(value),
          Ctor = result == objectTag ? value.constructor : undefined,
          ctorString = Ctor ? toSource(Ctor) : undefined;

      if (ctorString) {
        switch (ctorString) {
          case dataViewCtorString: return dataViewTag;
          case mapCtorString: return mapTag;
          case promiseCtorString: return promiseTag;
          case setCtorString: return setTag;
          case weakMapCtorString: return weakMapTag;
        }
      }
      return result;
    };
  }

  /**
   * Checks if `path` exists on `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @param {Array|string} path The path to check.
   * @param {Function} hasFunc The function to check properties.
   * @returns {boolean} Returns `true` if `path` exists, else `false`.
   */
  function hasPath(object, path, hasFunc) {
    path = isKey(path, object) ? [path] : castPath(path);

    var result,
        index = -1,
        length = path.length;

    while (++index < length) {
      var key = toKey(path[index]);
      if (!(result = object != null && hasFunc(object, key))) {
        break;
      }
      object = object[key];
    }
    if (result) {
      return result;
    }
    var length = object ? object.length : 0;
    return !!length && isLength(length) && isIndex(key, length) &&
      (isArray(object) || isArguments(object));
  }

  /**
   * Initializes an array clone.
   *
   * @private
   * @param {Array} array The array to clone.
   * @returns {Array} Returns the initialized clone.
   */
  function initCloneArray(array) {
    var length = array.length,
        result = array.constructor(length);

    // Add properties assigned by `RegExp#exec`.
    if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) {
      result.index = array.index;
      result.input = array.input;
    }
    return result;
  }

  /**
   * Initializes an object clone.
   *
   * @private
   * @param {Object} object The object to clone.
   * @returns {Object} Returns the initialized clone.
   */
  function initCloneObject(object) {
    return (typeof object.constructor == 'function' && !isPrototype(object))
      ? baseCreate(getPrototype(object))
      : {};
  }

  /**
   * Initializes an object clone based on its `toStringTag`.
   *
   * **Note:** This function only supports cloning values with tags of
   * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
   *
   * @private
   * @param {Object} object The object to clone.
   * @param {string} tag The `toStringTag` of the object to clone.
   * @param {Function} cloneFunc The function to clone values.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the initialized clone.
   */
  function initCloneByTag(object, tag, cloneFunc, isDeep) {
    var Ctor = object.constructor;
    switch (tag) {
      case arrayBufferTag:
        return cloneArrayBuffer(object);

      case boolTag:
      case dateTag:
        return new Ctor(+object);

      case dataViewTag:
        return cloneDataView(object, isDeep);

      case float32Tag: case float64Tag:
      case int8Tag: case int16Tag: case int32Tag:
      case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag:
        return cloneTypedArray(object, isDeep);

      case mapTag:
        return cloneMap(object, isDeep, cloneFunc);

      case numberTag:
      case stringTag:
        return new Ctor(object);

      case regexpTag:
        return cloneRegExp(object);

      case setTag:
        return cloneSet(object, isDeep, cloneFunc);

      case symbolTag:
        return cloneSymbol(object);
    }
  }

  /**
   * 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) {
    length = length == null ? MAX_SAFE_INTEGER : length;
    return !!length &&
      (typeof value == 'number' || 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;
  }

  /**
   * Checks if `value` is a property name and not a property path.
   *
   * @private
   * @param {*} value The value to check.
   * @param {Object} [object] The object to query keys on.
   * @returns {boolean} Returns `true` if `value` is a property name, else `false`.
   */
  function isKey(value, object) {
    if (isArray(value)) {
      return false;
    }
    var type = typeof value;
    if (type == 'number' || type == 'symbol' || type == 'boolean' ||
        value == null || isSymbol(value)) {
      return true;
    }
    return reIsPlainProp.test(value) || !reIsDeepProp.test(value) ||
      (object != null && value in Object(object));
  }

  /**
   * Checks if `value` is suitable for use as unique object key.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is suitable, else `false`.
   */
  function isKeyable(value) {
    var type = typeof value;
    return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean')
      ? (value !== '__proto__')
      : (value === null);
  }

  /**
   * Checks if `func` has its source masked.
   *
   * @private
   * @param {Function} func The function to check.
   * @returns {boolean} Returns `true` if `func` is masked, else `false`.
   */
  function isMasked(func) {
    return !!maskSrcKey && (maskSrcKey in func);
  }

  /**
   * Checks if `value` is likely a prototype object.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a prototype, else `false`.
   */
  function isPrototype(value) {
    var Ctor = value && value.constructor,
        proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto;

    return value === proto;
  }

  /**
   * Checks if `value` is suitable for strict equality comparisons, i.e. `===`.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` if suitable for strict
   *  equality comparisons, else `false`.
   */
  function isStrictComparable(value) {
    return value === value && !isObject(value);
  }

  /**
   * A specialized version of `matchesProperty` for source values suitable
   * for strict equality comparisons, i.e. `===`.
   *
   * @private
   * @param {string} key The key of the property to get.
   * @param {*} srcValue The value to match.
   * @returns {Function} Returns the new spec function.
   */
  function matchesStrictComparable(key, srcValue) {
    return function(object) {
      if (object == null) {
        return false;
      }
      return object[key] === srcValue &&
        (srcValue !== undefined || (key in Object(object)));
    };
  }

  /**
   * 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 `string` to a property path array.
   *
   * @private
   * @param {string} string The string to convert.
   * @returns {Array} Returns the property path array.
   */
  var stringToPath = memoize(function(string) {
    string = toString(string);

    var result = [];
    if (reLeadingDot.test(string)) {
      result.push('');
    }
    string.replace(rePropName, function(match, number, quote, string) {
      result.push(quote ? string.replace(reEscapeChar, '$1') : (number || match));
    });
    return result;
  });

  /**
   * Converts `value` to a string key if it's not a string or symbol.
   *
   * @private
   * @param {*} value The value to inspect.
   * @returns {string|symbol} Returns the key.
   */
  function toKey(value) {
    if (typeof value == 'string' || isSymbol(value)) {
      return value;
    }
    var result = (value + '');
    return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
  }

  /**
   * Converts `func` to its source code.
   *
   * @private
   * @param {Function} func The function to process.
   * @returns {string} Returns the source code.
   */
  function toSource(func) {
    if (func != null) {
      try {
        return funcToString.call(func);
      } catch (e) {}
      try {
        return (func + '');
      } catch (e) {}
    }
    return '';
  }

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

  /**
   * 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) {
    var index = -1,
        length = array ? array.length : 0,
        resIndex = 0,
        result = [];

    while (++index < length) {
      var value = array[index];
      if (value) {
        result[resIndex++] = value;
      }
    }
    return result;
  }

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

  /**
   * 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
   *
   * _([1, 2]).forEach(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) {
    var func = isArray(collection) ? arrayEach : baseEach;
    return func(collection, getIteratee(iteratee, 3));
  }

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

  /**
   * Creates a function that memoizes the result of `func`. If `resolver` is
   * provided, it determines the cache key for storing the result based on the
   * arguments provided to the memoized function. By default, the first argument
   * provided to the memoized function is used as the map cache key. The `func`
   * is invoked with the `this` binding of the memoized function.
   *
   * **Note:** The cache is exposed as the `cache` property on the memoized
   * function. Its creation may be customized by replacing the `_.memoize.Cache`
   * constructor with one whose instances implement the
   * [`Map`](http://ecma-international.org/ecma-262/7.0/#sec-properties-of-the-map-prototype-object)
   * method interface of `delete`, `get`, `has`, and `set`.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Function
   * @param {Function} func The function to have its output memoized.
   * @param {Function} [resolver] The function to resolve the cache key.
   * @returns {Function} Returns the new memoized function.
   * @example
   *
   * var object = { 'a': 1, 'b': 2 };
   * var other = { 'c': 3, 'd': 4 };
   *
   * var values = _.memoize(_.values);
   * values(object);
   * // => [1, 2]
   *
   * values(other);
   * // => [3, 4]
   *
   * object.a = 2;
   * values(object);
   * // => [1, 2]
   *
   * // Modify the result cache.
   * values.cache.set(object, ['a', 'b']);
   * values(object);
   * // => ['a', 'b']
   *
   * // Replace `_.memoize.Cache`.
   * _.memoize.Cache = WeakMap;
   */
  function memoize(func, resolver) {
    if (typeof func != 'function' || (resolver && typeof resolver != 'function')) {
      throw new TypeError(FUNC_ERROR_TEXT);
    }
    var memoized = function() {
      var args = arguments,
          key = resolver ? resolver.apply(this, args) : args[0],
          cache = memoized.cache;

      if (cache.has(key)) {
        return cache.get(key);
      }
      var result = func.apply(this, args);
      memoized.cache = cache.set(key, result);
      return result;
    };
    memoized.cache = new (memoize.Cache || MapCache);
    return memoized;
  }

  // Assign cache to `_.memoize`.
  memoize.Cache = MapCache;

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

  /**
   * 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) {
    return baseClone(value, false, true);
  }

  /**
   * 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
   */
  function isArguments(value) {
    // Safari 8.1 makes `arguments.callee` enumerable in strict mode.
    return isArrayLikeObject(value) && hasOwnProperty.call(value, 'callee') &&
      (!propertyIsEnumerable.call(value, 'callee') || objectToString.call(value) == argsTag);
  }

  /**
   * 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);
  }

  /**
   * This method is like `_.isArrayLike` except that it also checks if `value`
   * is an object.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array-like object,
   *  else `false`.
   * @example
   *
   * _.isArrayLikeObject([1, 2, 3]);
   * // => true
   *
   * _.isArrayLikeObject(document.body.children);
   * // => true
   *
   * _.isArrayLikeObject('abc');
   * // => false
   *
   * _.isArrayLikeObject(_.noop);
   * // => false
   */
  function isArrayLikeObject(value) {
    return isObjectLike(value) && isArrayLike(value);
  }

  /**
   * Checks if `value` is a buffer.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a buffer, else `false`.
   * @example
   *
   * _.isBuffer(new Buffer(2));
   * // => true
   *
   * _.isBuffer(new Uint8Array(2));
   * // => false
   */
  var isBuffer = nativeIsBuffer || stubFalse;

  /**
   * 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) || typeof value == 'string' ||
          typeof value.splice == 'function' || isBuffer(value) || isArguments(value))) {
      return !value.length;
    }
    var tag = getTag(value);
    if (tag == mapTag || tag == setTag) {
      return !value.size;
    }
    if (nonEnumShadows || isPrototype(value)) {
      return !nativeKeys(value).length;
    }
    for (var key in value) {
      if (hasOwnProperty.call(value, key)) {
        return false;
      }
    }
    return true;
  }

  /**
   * 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) {
    // The use of `Object#toString` avoids issues with the `typeof` operator
    // in Safari 8-9 which returns 'object' for typed array and other constructors.
    var tag = isObject(value) ? objectToString.call(value) : '';
    return tag == funcTag || tag == genTag;
  }

  /**
   * 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 && (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 && typeof value == 'object';
  }

  /**
   * Checks if `value` is a plain object, that is, an object created by the
   * `Object` constructor or one with a `[[Prototype]]` of `null`.
   *
   * @static
   * @memberOf _
   * @since 0.8.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
   * @example
   *
   * function Foo() {
   *   this.a = 1;
   * }
   *
   * _.isPlainObject(new Foo);
   * // => false
   *
   * _.isPlainObject([1, 2, 3]);
   * // => false
   *
   * _.isPlainObject({ 'x': 0, 'y': 0 });
   * // => true
   *
   * _.isPlainObject(Object.create(null));
   * // => true
   */
  function isPlainObject(value) {
    if (!isObjectLike(value) ||
        objectToString.call(value) != objectTag || isHostObject(value)) {
      return false;
    }
    var proto = getPrototype(value);
    if (proto === null) {
      return true;
    }
    var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;
    return (typeof Ctor == 'function' &&
      Ctor instanceof Ctor && funcToString.call(Ctor) == objectCtorString);
  }

  /**
   * Checks if `value` is classified as a `Symbol` primitive or object.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
   * @example
   *
   * _.isSymbol(Symbol.iterator);
   * // => true
   *
   * _.isSymbol('abc');
   * // => false
   */
  function isSymbol(value) {
    return typeof value == 'symbol' ||
      (isObjectLike(value) && objectToString.call(value) == symbolTag);
  }

  /**
   * Checks if `value` is classified as a typed array.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
   * @example
   *
   * _.isTypedArray(new Uint8Array);
   * // => true
   *
   * _.isTypedArray([]);
   * // => false
   */
  var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray;

  /**
   * Converts `value` to a plain object flattening inherited enumerable string
   * keyed properties of `value` to own properties of the plain object.
   *
   * @static
   * @memberOf _
   * @since 3.0.0
   * @category Lang
   * @param {*} value The value to convert.
   * @returns {Object} Returns the converted plain object.
   * @example
   *
   * function Foo() {
   *   this.b = 2;
   * }
   *
   * Foo.prototype.c = 3;
   *
   * _.assign({ 'a': 1 }, new Foo);
   * // => { 'a': 1, 'b': 2 }
   *
   * _.assign({ 'a': 1 }, _.toPlainObject(new Foo));
   * // => { 'a': 1, 'b': 2, 'c': 3 }
   */
  function toPlainObject(value) {
    return copyObject(value, keysIn(value));
  }

  /**
   * 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 process.
   * @returns {string} Returns the string.
   * @example
   *
   * _.toString(null);
   * // => ''
   *
   * _.toString(-0);
   * // => '-0'
   *
   * _.toString([1, 2, 3]);
   * // => '1,2,3'
   */
  function toString(value) {
    return value == null ? '' : baseToString(value);
  }

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

  /**
   * Gets the value at `path` of `object`. If the resolved value is
   * `undefined`, the `defaultValue` is returned in its place.
   *
   * @static
   * @memberOf _
   * @since 3.7.0
   * @category Object
   * @param {Object} object The object to query.
   * @param {Array|string} path The path of the property to get.
   * @param {*} [defaultValue] The value returned for `undefined` resolved values.
   * @returns {*} Returns the resolved value.
   * @example
   *
   * var object = { 'a': [{ 'b': { 'c': 3 } }] };
   *
   * _.get(object, 'a[0].b.c');
   * // => 3
   *
   * _.get(object, ['a', '0', 'b', 'c']);
   * // => 3
   *
   * _.get(object, 'a.b.c', 'default');
   * // => 'default'
   */
  function get(object, path, defaultValue) {
    var result = object == null ? undefined : baseGet(object, path);
    return result === undefined ? defaultValue : result;
  }

  /**
   * Checks if `path` is a direct or inherited property of `object`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @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 = _.create({ 'a': _.create({ 'b': 2 }) });
   *
   * _.hasIn(object, 'a');
   * // => true
   *
   * _.hasIn(object, 'a.b');
   * // => true
   *
   * _.hasIn(object, ['a', 'b']);
   * // => true
   *
   * _.hasIn(object, 'b');
   * // => false
   */
  function hasIn(object, path) {
    return object != null && hasPath(object, path, baseHasIn);
  }

  /**
   * 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']
   */
  function keys(object) {
    return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object);
  }

  /**
   * 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)
   */
  function keysIn(object) {
    return isArrayLike(object) ? arrayLikeKeys(object, true) : baseKeysIn(object);
  }

  /**
   * This method is like `_.assign` except that it recursively merges own and
   * inherited enumerable string keyed properties of source objects into the
   * destination object. Source properties that resolve to `undefined` are
   * skipped if a destination value exists. Array and plain object properties
   * are merged recursively. Other objects and value types are overridden by
   * assignment. Source objects are applied from left to right. Subsequent
   * sources overwrite property assignments of previous sources.
   *
   * **Note:** This method mutates `object`.
   *
   * @static
   * @memberOf _
   * @since 0.5.0
   * @category Object
   * @param {Object} object The destination object.
   * @param {...Object} [sources] The source objects.
   * @returns {Object} Returns `object`.
   * @example
   *
   * var object = {
   *   'a': [{ 'b': 2 }, { 'd': 4 }]
   * };
   *
   * var other = {
   *   'a': [{ 'c': 3 }, { 'e': 5 }]
   * };
   *
   * _.merge(object, other);
   * // => { 'a': [{ 'b': 2, 'c': 3 }, { 'd': 4, 'e': 5 }] }
   */
  var merge = createAssigner(function(object, source, srcIndex) {
    baseMerge(object, source, srcIndex);
  });

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

  /**
   * 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']
   */
  function iteratee(func) {
    return baseIteratee(typeof func == 'function' ? func : baseClone(func, true));
  }

  /**
   * Creates a function that returns the value at `path` of a given object.
   *
   * @static
   * @memberOf _
   * @since 2.4.0
   * @category Util
   * @param {Array|string} path The path of the property to get.
   * @returns {Function} Returns the new accessor function.
   * @example
   *
   * var objects = [
   *   { 'a': { 'b': 2 } },
   *   { 'a': { 'b': 1 } }
   * ];
   *
   * _.map(objects, _.property('a.b'));
   * // => [2, 1]
   *
   * _.map(_.sortBy(objects, _.property(['a', 'b'])), 'a.b');
   * // => [1, 2]
   */
  function property(path) {
    return isKey(path) ? baseProperty(toKey(path)) : basePropertyDeep(path);
  }

  /**
   * This method returns a new empty array.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {Array} Returns the new empty array.
   * @example
   *
   * var arrays = _.times(2, _.stubArray);
   *
   * console.log(arrays);
   * // => [[], []]
   *
   * console.log(arrays[0] === arrays[1]);
   * // => false
   */
  function stubArray() {
    return [];
  }

  /**
   * This method returns `false`.
   *
   * @static
   * @memberOf _
   * @since 4.13.0
   * @category Util
   * @returns {boolean} Returns `false`.
   * @example
   *
   * _.times(2, _.stubFalse);
   * // => [false, false]
   */
  function stubFalse() {
    return false;
  }

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

  // Add methods that return wrapped values in chain sequences.
  lodash.compact = compact;
  lodash.iteratee = iteratee;
  lodash.keys = keys;
  lodash.keysIn = keysIn;
  lodash.memoize = memoize;
  lodash.merge = merge;
  lodash.property = property;
  lodash.toPlainObject = toPlainObject;

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

  // Add methods that return unwrapped values in chain sequences.
  lodash.clone = clone;
  lodash.eq = eq;
  lodash.forEach = forEach;
  lodash.get = get;
  lodash.hasIn = hasIn;
  lodash.identity = identity;
  lodash.isArguments = isArguments;
  lodash.isArray = isArray;
  lodash.isArrayLike = isArrayLike;
  lodash.isArrayLikeObject = isArrayLikeObject;
  lodash.isBuffer = isBuffer;
  lodash.isEmpty = isEmpty;
  lodash.isFunction = isFunction;
  lodash.isLength = isLength;
  lodash.isObject = isObject;
  lodash.isObjectLike = isObjectLike;
  lodash.isPlainObject = isPlainObject;
  lodash.isSymbol = isSymbol;
  lodash.isTypedArray = isTypedArray;
  lodash.stubArray = stubArray;
  lodash.stubFalse = stubFalse;
  lodash.toString = toString;

  // Add aliases.
  lodash.each = forEach;

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

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

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

  if (freeModule) {
    // Export for Node.js.
    (freeModule.exports = lodash)._ = lodash;
    // Export for CommonJS support.
    freeExports._ = lodash;
  }
}.call(this));