bk2018/node_modules/objection/lib/utils/clone.js

/**
 * @license
 * Lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash include="cloneDeep,clone" exports="node" --development`
 * Copyright JS Foundation and other contributors <https://js.foundation/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */
(function() {
  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
  var undefined;

  /** Used as the semantic version number. */
  var VERSION = '4.17.5';

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

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

  /** Used to compose bitmasks for cloning. */
  var CLONE_DEEP_FLAG = 1,
    CLONE_FLAT_FLAG = 2,
    CLONE_SYMBOLS_FLAG = 4;

  /** Used as references for various `Number` constants. */
  var MAX_SAFE_INTEGER = 9007199254740991;

  /** `Object#toString` result references. */
  var argsTag = '[object Arguments]',
    arrayTag = '[object Array]',
    asyncTag = '[object AsyncFunction]',
    boolTag = '[object Boolean]',
    dateTag = '[object Date]',
    errorTag = '[object Error]',
    funcTag = '[object Function]',
    genTag = '[object GeneratorFunction]',
    mapTag = '[object Map]',
    numberTag = '[object Number]',
    nullTag = '[object Null]',
    objectTag = '[object Object]',
    promiseTag = '[object Promise]',
    proxyTag = '[object Proxy]',
    regexpTag = '[object RegExp]',
    setTag = '[object Set]',
    stringTag = '[object String]',
    symbolTag = '[object Symbol]',
    undefinedTag = '[object Undefined]',
    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 `RegExp`
   * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns).
   */
  var reRegExpChar = /[\\^$.*+?()[\]{}|]/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;

  /** Used as a reference to the global object. */
  var root = freeGlobal || 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 && freeProcess.binding('util');
    } catch (e) {}
  })();

  /* Node.js helper references. */
  var nodeIsMap = nodeUtil && nodeUtil.isMap,
    nodeIsSet = nodeUtil && nodeUtil.isSet,
    nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;

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

  /**
   * 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 == null ? 0 : array.length;

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

  /**
   * A specialized version of `_.filter` 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 {Array} Returns the new filtered array.
   */
  function arrayFilter(array, predicate) {
    var index = -1,
      length = array == null ? 0 : array.length,
      resIndex = 0,
      result = [];

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

  /**
   * 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;
  }

  /**
   * 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];
  }

  /**
   * Creates a unary function that invokes `func` with its argument transformed.
   *
   * @private
   * @param {Function} func The function to wrap.
   * @param {Function} transform The argument transform.
   * @returns {Function} Returns the new function.
   */
  function overArg(func, transform) {
    return function(arg) {
      return func(transform(arg));
    };
  }

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

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

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

  /** 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 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
   * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
   * of values.
   */
  var nativeObjectToString = 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,
    allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined,
    getPrototype = overArg(Object.getPrototypeOf, Object),
    objectCreate = Object.create,
    propertyIsEnumerable = objectProto.propertyIsEnumerable,
    splice = arrayProto.splice,
    symToStringTag = Symbol ? Symbol.toStringTag : undefined;

  var defineProperty = (function() {
    try {
      var func = getNative(Object, 'defineProperty');
      func({}, '', {});
      return func;
    } catch (e) {}
  })();

  /* 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);

  /* 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');

  /** 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;

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

  /**
   * Creates a `lodash` object which wraps `value` to enable implicit method
   * chain sequences. Methods that operate on and return arrays, collections,
   * and functions can be chained together. Methods that retrieve a single value
   * or may return a primitive value will automatically end the chain sequence
   * and return the unwrapped value. Otherwise, the value must be unwrapped
   * with `_#value`.
   *
   * Explicit chain sequences, which must be unwrapped with `_#value`, may be
   * enabled using `_.chain`.
   *
   * The execution of chained methods is lazy, that is, it's deferred until
   * `_#value` is implicitly or explicitly called.
   *
   * Lazy evaluation allows several methods to support shortcut fusion.
   * Shortcut fusion is an optimization to merge iteratee calls; this avoids
   * the creation of intermediate arrays and can greatly reduce the number of
   * iteratee executions. Sections of a chain sequence qualify for shortcut
   * fusion if the section is applied to an array and iteratees accept only
   * one argument. The heuristic for whether a section qualifies for shortcut
   * fusion is subject to change.
   *
   * Chaining is supported in custom builds as long as the `_#value` method is
   * directly or indirectly included in the build.
   *
   * In addition to lodash methods, wrappers have `Array` and `String` methods.
   *
   * The wrapper `Array` methods are:
   * `concat`, `join`, `pop`, `push`, `shift`, `sort`, `splice`, and `unshift`
   *
   * The wrapper `String` methods are:
   * `replace` and `split`
   *
   * The wrapper methods that support shortcut fusion are:
   * `at`, `compact`, `drop`, `dropRight`, `dropWhile`, `filter`, `find`,
   * `findLast`, `head`, `initial`, `last`, `map`, `reject`, `reverse`, `slice`,
   * `tail`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, and `toArray`
   *
   * The chainable wrapper methods are:
   * `after`, `ary`, `assign`, `assignIn`, `assignInWith`, `assignWith`, `at`,
   * `before`, `bind`, `bindAll`, `bindKey`, `castArray`, `chain`, `chunk`,
   * `commit`, `compact`, `concat`, `conforms`, `constant`, `countBy`, `create`,
   * `curry`, `debounce`, `defaults`, `defaultsDeep`, `defer`, `delay`,
   * `difference`, `differenceBy`, `differenceWith`, `drop`, `dropRight`,
   * `dropRightWhile`, `dropWhile`, `extend`, `extendWith`, `fill`, `filter`,
   * `flatMap`, `flatMapDeep`, `flatMapDepth`, `flatten`, `flattenDeep`,
   * `flattenDepth`, `flip`, `flow`, `flowRight`, `fromPairs`, `functions`,
   * `functionsIn`, `groupBy`, `initial`, `intersection`, `intersectionBy`,
   * `intersectionWith`, `invert`, `invertBy`, `invokeMap`, `iteratee`, `keyBy`,
   * `keys`, `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`,
   * `memoize`, `merge`, `mergeWith`, `method`, `methodOf`, `mixin`, `negate`,
   * `nthArg`, `omit`, `omitBy`, `once`, `orderBy`, `over`, `overArgs`,
   * `overEvery`, `overSome`, `partial`, `partialRight`, `partition`, `pick`,
   * `pickBy`, `plant`, `property`, `propertyOf`, `pull`, `pullAll`, `pullAllBy`,
   * `pullAllWith`, `pullAt`, `push`, `range`, `rangeRight`, `rearg`, `reject`,
   * `remove`, `rest`, `reverse`, `sampleSize`, `set`, `setWith`, `shuffle`,
   * `slice`, `sort`, `sortBy`, `splice`, `spread`, `tail`, `take`, `takeRight`,
   * `takeRightWhile`, `takeWhile`, `tap`, `throttle`, `thru`, `toArray`,
   * `toPairs`, `toPairsIn`, `toPath`, `toPlainObject`, `transform`, `unary`,
   * `union`, `unionBy`, `unionWith`, `uniq`, `uniqBy`, `uniqWith`, `unset`,
   * `unshift`, `unzip`, `unzipWith`, `update`, `updateWith`, `values`,
   * `valuesIn`, `without`, `wrap`, `xor`, `xorBy`, `xorWith`, `zip`,
   * `zipObject`, `zipObjectDeep`, and `zipWith`
   *
   * The wrapper methods that are **not** chainable by default are:
   * `add`, `attempt`, `camelCase`, `capitalize`, `ceil`, `clamp`, `clone`,
   * `cloneDeep`, `cloneDeepWith`, `cloneWith`, `conformsTo`, `deburr`,
   * `defaultTo`, `divide`, `each`, `eachRight`, `endsWith`, `eq`, `escape`,
   * `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`, `findLast`,
   * `findLastIndex`, `findLastKey`, `first`, `floor`, `forEach`, `forEachRight`,
   * `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `get`, `gt`, `gte`, `has`,
   * `hasIn`, `head`, `identity`, `includes`, `indexOf`, `inRange`, `invoke`,
   * `isArguments`, `isArray`, `isArrayBuffer`, `isArrayLike`, `isArrayLikeObject`,
   * `isBoolean`, `isBuffer`, `isDate`, `isElement`, `isEmpty`, `isEqual`,
   * `isEqualWith`, `isError`, `isFinite`, `isFunction`, `isInteger`, `isLength`,
   * `isMap`, `isMatch`, `isMatchWith`, `isNaN`, `isNative`, `isNil`, `isNull`,
   * `isNumber`, `isObject`, `isObjectLike`, `isPlainObject`, `isRegExp`,
   * `isSafeInteger`, `isSet`, `isString`, `isUndefined`, `isTypedArray`,
   * `isWeakMap`, `isWeakSet`, `join`, `kebabCase`, `last`, `lastIndexOf`,
   * `lowerCase`, `lowerFirst`, `lt`, `lte`, `max`, `maxBy`, `mean`, `meanBy`,
   * `min`, `minBy`, `multiply`, `noConflict`, `noop`, `now`, `nth`, `pad`,
   * `padEnd`, `padStart`, `parseInt`, `pop`, `random`, `reduce`, `reduceRight`,
   * `repeat`, `result`, `round`, `runInContext`, `sample`, `shift`, `size`,
   * `snakeCase`, `some`, `sortedIndex`, `sortedIndexBy`, `sortedLastIndex`,
   * `sortedLastIndexBy`, `startCase`, `startsWith`, `stubArray`, `stubFalse`,
   * `stubObject`, `stubString`, `stubTrue`, `subtract`, `sum`, `sumBy`,
   * `template`, `times`, `toFinite`, `toInteger`, `toJSON`, `toLength`,
   * `toLower`, `toNumber`, `toSafeInteger`, `toString`, `toUpper`, `trim`,
   * `trimEnd`, `trimStart`, `truncate`, `unescape`, `uniqueId`, `upperCase`,
   * `upperFirst`, `value`, and `words`
   *
   * @name _
   * @constructor
   * @category Seq
   * @param {*} value The value to wrap in a `lodash` instance.
   * @returns {Object} Returns the new `lodash` wrapper instance.
   * @example
   *
   * function square(n) {
   *   return n * n;
   * }
   *
   * var wrapped = _([1, 2, 3]);
   *
   * // Returns an unwrapped value.
   * wrapped.reduce(_.add);
   * // => 6
   *
   * // Returns a wrapped value.
   * var squares = wrapped.map(square);
   *
   * _.isArray(squares);
   * // => false
   *
   * _.isArray(squares.value());
   * // => true
   */
  function lodash() {
    // No operation performed.
  }

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

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

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

    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) : {};
    this.size = 0;
  }

  /**
   * 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) {
    var result = this.has(key) && delete this.__data__[key];
    this.size -= result ? 1 : 0;
    return result;
  }

  /**
   * 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__;
    this.size += this.has(key) ? 0 : 1;
    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 == null ? 0 : entries.length;

    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__ = [];
    this.size = 0;
  }

  /**
   * 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);
    }
    --this.size;
    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) {
      ++this.size;
      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 == null ? 0 : entries.length;

    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.size = 0;
    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) {
    var result = getMapData(this, key)['delete'](key);
    this.size -= result ? 1 : 0;
    return result;
  }

  /**
   * 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) {
    var data = getMapData(this, key),
      size = data.size;

    data.set(key, value);
    this.size += data.size == size ? 0 : 1;
    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 a stack cache object to store key-value pairs.
   *
   * @private
   * @constructor
   * @param {Array} [entries] The key-value pairs to cache.
   */
  function Stack(entries) {
    var data = (this.__data__ = new ListCache(entries));
    this.size = data.size;
  }

  /**
   * Removes all key-value entries from the stack.
   *
   * @private
   * @name clear
   * @memberOf Stack
   */
  function stackClear() {
    this.__data__ = new ListCache();
    this.size = 0;
  }

  /**
   * 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) {
    var data = this.__data__,
      result = data['delete'](key);

    this.size = data.size;
    return result;
  }

  /**
   * 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 data = this.__data__;
    if (data instanceof ListCache) {
      var pairs = data.__data__;
      if (!Map || pairs.length < LARGE_ARRAY_SIZE - 1) {
        pairs.push([key, value]);
        this.size = ++data.size;
        return this;
      }
      data = this.__data__ = new MapCache(pairs);
    }
    data.set(key, value);
    this.size = data.size;
    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) {
    var isArr = isArray(value),
      isArg = !isArr && isArguments(value),
      isBuff = !isArr && !isArg && isBuffer(value),
      isType = !isArr && !isArg && !isBuff && isTypedArray(value),
      skipIndexes = isArr || isArg || isBuff || isType,
      result = skipIndexes ? baseTimes(value.length, String) : [],
      length = result.length;

    for (var key in value) {
      if (
        (inherited || hasOwnProperty.call(value, key)) &&
        !(
          skipIndexes &&
          // Safari 9 has enumerable `arguments.length` in strict mode.
          (key == 'length' ||
            // Node.js 0.10 has enumerable non-index properties on buffers.
            (isBuff && (key == 'offset' || key == 'parent')) ||
            // PhantomJS 2 has enumerable non-index properties on typed arrays.
            (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
            // Skip index properties.
            isIndex(key, length))
        )
      ) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * Assigns `value` to `key` of `object` if the existing value is not equivalent
   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * for equality comparisons.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {string} key The key of the property to assign.
   * @param {*} value The value to assign.
   */
  function assignValue(object, key, value) {
    var objValue = object[key];
    if (
      !(hasOwnProperty.call(object, key) && eq(objValue, value)) ||
      (value === undefined && !(key in object))
    ) {
      baseAssignValue(object, key, value);
    }
  }

  /**
   * 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 `_.assignIn` 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 baseAssignIn(object, source) {
    return object && copyObject(source, keysIn(source), object);
  }

  /**
   * The base implementation of `assignValue` and `assignMergeValue` without
   * value checks.
   *
   * @private
   * @param {Object} object The object to modify.
   * @param {string} key The key of the property to assign.
   * @param {*} value The value to assign.
   */
  function baseAssignValue(object, key, value) {
    if (key == '__proto__' && defineProperty) {
      defineProperty(object, key, {
        configurable: true,
        enumerable: true,
        value: value,
        writable: true
      });
    } else {
      object[key] = value;
    }
  }

  /**
   * The base implementation of `_.clone` and `_.cloneDeep` which tracks
   * traversed objects.
   *
   * @private
   * @param {*} value The value to clone.
   * @param {boolean} bitmask The bitmask flags.
   *  1 - Deep clone
   *  2 - Flatten inherited properties
   *  4 - Clone 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, bitmask, customizer, key, object, stack) {
    var result,
      isDeep = bitmask & CLONE_DEEP_FLAG,
      isFlat = bitmask & CLONE_FLAT_FLAG,
      isFull = bitmask & CLONE_SYMBOLS_FLAG;

    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)) {
        result = isFlat || isFunc ? {} : initCloneObject(value);
        if (!isDeep) {
          return isFlat
            ? copySymbolsIn(value, baseAssignIn(result, value))
            : copySymbols(value, baseAssign(result, value));
        }
      } else {
        if (!cloneableTags[tag]) {
          return object ? value : {};
        }
        result = initCloneByTag(value, tag, 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 (isSet(value)) {
      value.forEach(function(subValue) {
        result.add(baseClone(subValue, bitmask, customizer, subValue, value, stack));
      });

      return result;
    }

    if (isMap(value)) {
      value.forEach(function(subValue, key) {
        result.set(key, baseClone(subValue, bitmask, customizer, key, value, stack));
      });

      return result;
    }

    var keysFunc = isFull ? (isFlat ? getAllKeysIn : getAllKeys) : isFlat ? keysIn : keys;

    var props = isArr ? undefined : keysFunc(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, bitmask, customizer, key, value, stack));
    });
    return result;
  }

  /**
   * 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` without fallbacks for buggy environments.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the `toStringTag`.
   */
  function baseGetTag(value) {
    if (value == null) {
      return value === undefined ? undefinedTag : nullTag;
    }
    return symToStringTag && symToStringTag in Object(value)
      ? getRawTag(value)
      : objectToString(value);
  }

  /**
   * The base implementation of `_.isArguments`.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an `arguments` object,
   */
  function baseIsArguments(value) {
    return isObjectLike(value) && baseGetTag(value) == argsTag;
  }

  /**
   * The base implementation of `_.isMap` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a map, else `false`.
   */
  function baseIsMap(value) {
    return isObjectLike(value) && getTag(value) == mapTag;
  }

  /**
   * 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) ? reIsNative : reIsHostCtor;
    return pattern.test(toSource(value));
  }

  /**
   * The base implementation of `_.isSet` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a set, else `false`.
   */
  function baseIsSet(value) {
    return isObjectLike(value) && getTag(value) == setTag;
  }

  /**
   * 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[baseGetTag(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;
  }

  /**
   * 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 length = buffer.length,
      result = allocUnsafe ? allocUnsafe(length) : new buffer.constructor(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 `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 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) {
    var isNew = !object;
    object || (object = {});

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

    while (++index < length) {
      var key = props[index];

      var newValue = customizer
        ? customizer(object[key], source[key], key, object, source)
        : undefined;

      if (newValue === undefined) {
        newValue = source[key];
      }
      if (isNew) {
        baseAssignValue(object, key, newValue);
      } else {
        assignValue(object, key, newValue);
      }
    }
    return object;
  }

  /**
   * Copies own symbols 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);
  }

  /**
   * Copies own and inherited symbols 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 copySymbolsIn(source, object) {
    return copyObject(source, getSymbolsIn(source), object);
  }

  /**
   * 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);
  }

  /**
   * Creates an array of own and inherited 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 getAllKeysIn(object) {
    return baseGetAllKeys(object, keysIn, getSymbolsIn);
  }

  /**
   * 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 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;
  }

  /**
   * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values.
   *
   * @private
   * @param {*} value The value to query.
   * @returns {string} Returns the raw `toStringTag`.
   */
  function getRawTag(value) {
    var isOwn = hasOwnProperty.call(value, symToStringTag),
      tag = value[symToStringTag];

    try {
      value[symToStringTag] = undefined;
      var unmasked = true;
    } catch (e) {}

    var result = nativeObjectToString.call(value);
    if (unmasked) {
      if (isOwn) {
        value[symToStringTag] = tag;
      } else {
        delete value[symToStringTag];
      }
    }
    return result;
  }

  /**
   * Creates an array of the own enumerable symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of symbols.
   */
  var getSymbols = !nativeGetSymbols
    ? stubArray
    : function(object) {
        if (object == null) {
          return [];
        }
        object = Object(object);
        return arrayFilter(nativeGetSymbols(object), function(symbol) {
          return propertyIsEnumerable.call(object, symbol);
        });
      };

  /**
   * Creates an array of the own and inherited enumerable symbols of `object`.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of symbols.
   */
  var getSymbolsIn = !nativeGetSymbols
    ? stubArray
    : function(object) {
        var result = [];
        while (object) {
          arrayPush(result, getSymbols(object));
          object = getPrototype(object);
        }
        return result;
      };

  /**
   * 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 and promises in Node.js < 6.
  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 = baseGetTag(value),
        Ctor = result == objectTag ? value.constructor : undefined,
        ctorString = Ctor ? toSource(Ctor) : '';

      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;
    };
  }

  /**
   * 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 = new 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`, `Map`, `Number`, `RegExp`, `Set`, or `String`.
   *
   * @private
   * @param {Object} object The object to clone.
   * @param {string} tag The `toStringTag` of the object to clone.
   * @param {boolean} [isDeep] Specify a deep clone.
   * @returns {Object} Returns the initialized clone.
   */
  function initCloneByTag(object, tag, 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 new Ctor();

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

      case regexpTag:
        return cloneRegExp(object);

      case setTag:
        return new Ctor();

      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) {
    var type = typeof value;
    length = length == null ? MAX_SAFE_INTEGER : length;

    return (
      !!length &&
      (type == 'number' || (type != 'symbol' && reIsUint.test(value))) &&
      (value > -1 && value % 1 == 0 && value < length)
    );
  }

  /**
   * Checks if `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;
  }

  /**
   * This function is like
   * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
   * except that it includes inherited enumerable properties.
   *
   * @private
   * @param {Object} object The object to query.
   * @returns {Array} Returns the array of property names.
   */
  function nativeKeysIn(object) {
    var result = [];
    if (object != null) {
      for (var key in Object(object)) {
        result.push(key);
      }
    }
    return result;
  }

  /**
   * Converts `value` to a string using `Object.prototype.toString`.
   *
   * @private
   * @param {*} value The value to convert.
   * @returns {string} Returns the converted string.
   */
  function objectToString(value) {
    return nativeObjectToString.call(value);
  }

  /**
   * Converts `func` to its source code.
   *
   * @private
   * @param {Function} func The function to convert.
   * @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 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, CLONE_SYMBOLS_FLAG);
  }

  /**
   * This method is like `_.clone` except that it recursively clones `value`.
   *
   * @static
   * @memberOf _
   * @since 1.0.0
   * @category Lang
   * @param {*} value The value to recursively clone.
   * @returns {*} Returns the deep cloned value.
   * @see _.clone
   * @example
   *
   * var objects = [{ 'a': 1 }, { 'b': 2 }];
   *
   * var deep = _.cloneDeep(objects);
   * console.log(deep[0] === objects[0]);
   * // => false
   */
  function cloneDeep(value) {
    return baseClone(value, CLONE_DEEP_FLAG | CLONE_SYMBOLS_FLAG);
  }

  /**
   * Performs a
   * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
   * comparison between two values to determine if they are equivalent.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to compare.
   * @param {*} other The other value to compare.
   * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
   * @example
   *
   * var object = { 'a': 1 };
   * var other = { 'a': 1 };
   *
   * _.eq(object, object);
   * // => true
   *
   * _.eq(object, other);
   * // => false
   *
   * _.eq('a', 'a');
   * // => true
   *
   * _.eq('a', Object('a'));
   * // => false
   *
   * _.eq(NaN, NaN);
   * // => true
   */
  function eq(value, other) {
    return value === other || (value !== value && other !== other);
  }

  /**
   * Checks if `value` is likely an `arguments` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an `arguments` object,
   *  else `false`.
   * @example
   *
   * _.isArguments(function() { return arguments; }());
   * // => true
   *
   * _.isArguments([1, 2, 3]);
   * // => false
   */
  var isArguments = baseIsArguments(
    (function() {
      return arguments;
    })()
  )
    ? baseIsArguments
    : function(value) {
        return (
          isObjectLike(value) &&
          hasOwnProperty.call(value, 'callee') &&
          !propertyIsEnumerable.call(value, 'callee')
        );
      };

  /**
   * Checks if `value` is classified as an `Array` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an array, else `false`.
   * @example
   *
   * _.isArray([1, 2, 3]);
   * // => true
   *
   * _.isArray(document.body.children);
   * // => false
   *
   * _.isArray('abc');
   * // => false
   *
   * _.isArray(_.noop);
   * // => false
   */
  var isArray = Array.isArray;

  /**
   * Checks if `value` is array-like. A value is considered array-like if it's
   * not a function and has a `value.length` that's an integer greater than or
   * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`.
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is array-like, else `false`.
   * @example
   *
   * _.isArrayLike([1, 2, 3]);
   * // => true
   *
   * _.isArrayLike(document.body.children);
   * // => true
   *
   * _.isArrayLike('abc');
   * // => true
   *
   * _.isArrayLike(_.noop);
   * // => false
   */
  function isArrayLike(value) {
    return value != null && isLength(value.length) && !isFunction(value);
  }

  /**
   * Checks if `value` is 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 classified as a `Function` object.
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a function, else `false`.
   * @example
   *
   * _.isFunction(_);
   * // => true
   *
   * _.isFunction(/abc/);
   * // => false
   */
  function isFunction(value) {
    if (!isObject(value)) {
      return false;
    }
    // The use of `Object#toString` avoids issues with the `typeof` operator
    // in Safari 9 which returns 'object' for typed arrays and other constructors.
    var tag = baseGetTag(value);
    return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag;
  }

  /**
   * Checks if `value` is a valid array-like length.
   *
   * **Note:** This method is loosely based on
   * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
   * @example
   *
   * _.isLength(3);
   * // => true
   *
   * _.isLength(Number.MIN_VALUE);
   * // => false
   *
   * _.isLength(Infinity);
   * // => false
   *
   * _.isLength('3');
   * // => false
   */
  function isLength(value) {
    return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
  }

  /**
   * Checks if `value` is the
   * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
   * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
   *
   * @static
   * @memberOf _
   * @since 0.1.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is an object, else `false`.
   * @example
   *
   * _.isObject({});
   * // => true
   *
   * _.isObject([1, 2, 3]);
   * // => true
   *
   * _.isObject(_.noop);
   * // => true
   *
   * _.isObject(null);
   * // => false
   */
  function isObject(value) {
    var type = typeof value;
    return value != null && (type == 'object' || type == 'function');
  }

  /**
   * Checks if `value` is object-like. A value is object-like if it's not `null`
   * and has a `typeof` result of "object".
   *
   * @static
   * @memberOf _
   * @since 4.0.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
   * @example
   *
   * _.isObjectLike({});
   * // => true
   *
   * _.isObjectLike([1, 2, 3]);
   * // => true
   *
   * _.isObjectLike(_.noop);
   * // => false
   *
   * _.isObjectLike(null);
   * // => false
   */
  function isObjectLike(value) {
    return value != null && typeof value == 'object';
  }

  /**
   * Checks if `value` is classified as a `Map` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a map, else `false`.
   * @example
   *
   * _.isMap(new Map);
   * // => true
   *
   * _.isMap(new WeakMap);
   * // => false
   */
  var isMap = nodeIsMap ? baseUnary(nodeIsMap) : baseIsMap;

  /**
   * Checks if `value` is classified as a `Set` object.
   *
   * @static
   * @memberOf _
   * @since 4.3.0
   * @category Lang
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a set, else `false`.
   * @example
   *
   * _.isSet(new Set);
   * // => true
   *
   * _.isSet(new WeakSet);
   * // => false
   */
  var isSet = nodeIsSet ? baseUnary(nodeIsSet) : baseIsSet;

  /**
   * 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;

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

  /**
   * 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 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.keys = keys;
  lodash.keysIn = keysIn;

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

  // Add methods that return unwrapped values in chain sequences.
  lodash.clone = clone;
  lodash.cloneDeep = cloneDeep;
  lodash.eq = eq;
  lodash.isArguments = isArguments;
  lodash.isArray = isArray;
  lodash.isArrayLike = isArrayLike;
  lodash.isBuffer = isBuffer;
  lodash.isFunction = isFunction;
  lodash.isLength = isLength;
  lodash.isMap = isMap;
  lodash.isObject = isObject;
  lodash.isObjectLike = isObjectLike;
  lodash.isSet = isSet;
  lodash.isTypedArray = isTypedArray;
  lodash.stubArray = stubArray;
  lodash.stubFalse = stubFalse;

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

  /**
   * 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));