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/**
 * Lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o packages`
 * Copyright OpenJS Foundation and other contributors <https://openjsf.org/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */

/** 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 detect hot functions by number of calls within a span of milliseconds. */
var HOT_COUNT = 800,
    HOT_SPAN = 16;

/** Used as references for various `Number` constants. */
var INFINITY = 1 / 0,
    MAX_SAFE_INTEGER = 9007199254740991;

/** `Object#toString` result references. */
var argsTag = '[object Arguments]',
    asyncTag = '[object AsyncFunction]',
    funcTag = '[object Function]',
    genTag = '[object GeneratorFunction]',
    nullTag = '[object Null]',
    proxyTag = '[object Proxy]',
    undefinedTag = '[object Undefined]';

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

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

/** Detect free variable `global` from Node.js. */
var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;

/** Detect free variable `globalThis` */
const freeGlobalThis = typeof globalThis == 'object' && globalThis !== null && globalThis.Object == Object && globalThis;

/** Detect free variable `self`. */
var freeSelf = typeof self == 'object' && self && self.Object === Object && self;

/** Used as a reference to the global object. */
var root = freeGlobalThis || freeGlobal || freeSelf || Function('return this')();

/**
 * 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 `_.includes` for arrays without support for
 * specifying an index to search from.
 *
 * @private
 * @param {Array} [array] The array to inspect.
 * @param {*} target The value to search for.
 * @returns {boolean} Returns `true` if `target` is found, else `false`.
 */
function arrayIncludes(array, value) {
  var length = array == null ? 0 : array.length;
  return !!length && baseIndexOf(array, value, 0) > -1;
}

/**
 * This function is like `arrayIncludes` except that it accepts a comparator.
 *
 * @private
 * @param {Array} [array] The array to inspect.
 * @param {*} target The value to search for.
 * @param {Function} comparator The comparator invoked per element.
 * @returns {boolean} Returns `true` if `target` is found, else `false`.
 */
function arrayIncludesWith(array, value, comparator) {
  var index = -1,
      length = array == null ? 0 : array.length;

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

/**
 * 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 `_.findIndex` and `_.findLastIndex` without
 * support for iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {Function} predicate The function invoked per iteration.
 * @param {number} fromIndex The index to search from.
 * @param {boolean} [fromRight] Specify iterating from right to left.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function baseFindIndex(array, predicate, fromIndex, fromRight) {
  var length = array.length,
      index = fromIndex + (fromRight ? 1 : -1);

  while ((fromRight ? index-- : ++index < length)) {
    if (predicate(array[index], index, array)) {
      return index;
    }
  }
  return -1;
}

/**
 * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function baseIndexOf(array, value, fromIndex) {
  return value === value
    ? strictIndexOf(array, value, fromIndex)
    : baseFindIndex(array, baseIsNaN, fromIndex);
}

/**
 * The base implementation of `_.isNaN` without support for number objects.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
 */
function baseIsNaN(value) {
  return value !== value;
}

/**
 * Checks if a `cache` value for `key` exists.
 *
 * @private
 * @param {Object} cache The cache to query.
 * @param {string} key The key of the entry to check.
 * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
 */
function cacheHas(cache, key) {
  return cache.has(key);
}

/**
 * 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];
}

/**
 * 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;
}

/**
 * A specialized version of `_.indexOf` which performs strict equality
 * comparisons of values, i.e. `===`.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {*} value The value to search for.
 * @param {number} fromIndex The index to search from.
 * @returns {number} Returns the index of the matched value, else `-1`.
 */
function strictIndexOf(array, value, fromIndex) {
  var index = fromIndex - 1,
      length = array.length;

  while (++index < length) {
    if (array[index] === value) {
      return index;
    }
  }
  return -1;
}

/** 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 Symbol = root.Symbol,
    propertyIsEnumerable = objectProto.propertyIsEnumerable,
    splice = arrayProto.splice,
    spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined,
    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 nativeMax = Math.max,
    nativeNow = Date.now;

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

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

  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;

/**
 * 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 `_.flatten` with support for restricting flattening.
 *
 * @private
 * @param {Array} array The array to flatten.
 * @param {number} depth The maximum recursion depth.
 * @param {boolean} [predicate=isFlattenable] The function invoked per iteration.
 * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks.
 * @param {Array} [result=[]] The initial result value.
 * @returns {Array} Returns the new flattened array.
 */
function baseFlatten(array, depth, predicate, isStrict, result) {
  var index = -1,
      length = array.length;

  predicate || (predicate = isFlattenable);
  result || (result = []);

  while (++index < length) {
    var value = array[index];
    if (depth > 0 && predicate(value)) {
      if (depth > 1) {
        // Recursively flatten arrays (susceptible to call stack limits).
        baseFlatten(value, depth - 1, predicate, isStrict, result);
      } else {
        arrayPush(result, value);
      }
    } else if (!isStrict) {
      result[result.length] = value;
    }
  }
  return result;
}

/**
 * The base implementation of `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 `_.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 `_.rest` which doesn't validate or coerce arguments.
 *
 * @private
 * @param {Function} func The function to apply a rest parameter to.
 * @param {number} [start=func.length-1] The start position of the rest parameter.
 * @returns {Function} Returns the new function.
 */
function baseRest(func, start) {
  return setToString(overRest(func, start, identity), func + '');
}

/**
 * The base implementation of `setToString` without support for hot loop shorting.
 *
 * @private
 * @param {Function} func The function to modify.
 * @param {Function} string The `toString` result.
 * @returns {Function} Returns `func`.
 */
var baseSetToString = !defineProperty ? identity : function(func, string) {
  return defineProperty(func, 'toString', {
    'configurable': true,
    'enumerable': false,
    'value': constant(string),
    'writable': true
  });
};

/**
 * The base implementation of `_.uniqBy` without support for iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to inspect.
 * @param {Function} [iteratee] The iteratee invoked per element.
 * @param {Function} [comparator] The comparator invoked per element.
 * @returns {Array} Returns the new duplicate free array.
 */
function baseUniq(array, iteratee, comparator) {
  var index = -1,
      includes = arrayIncludes,
      length = array.length,
      isCommon = true,
      result = [],
      seen = result;

  if (comparator) {
    isCommon = false;
    includes = arrayIncludesWith;
  }
  else if (length >= LARGE_ARRAY_SIZE) {
    var set = iteratee ? null : createSet(array);
    if (set) {
      return setToArray(set);
    }
    isCommon = false;
    includes = cacheHas;
    seen = new SetCache;
  }
  else {
    seen = iteratee ? [] : result;
  }
  outer:
  while (++index < length) {
    var value = array[index],
        computed = iteratee ? iteratee(value) : value;

    value = (comparator || value !== 0) ? value : 0;
    if (isCommon && computed === computed) {
      var seenIndex = seen.length;
      while (seenIndex--) {
        if (seen[seenIndex] === computed) {
          continue outer;
        }
      }
      if (iteratee) {
        seen.push(computed);
      }
      result.push(value);
    }
    else if (!includes(seen, computed, comparator)) {
      if (seen !== result) {
        seen.push(computed);
      }
      result.push(value);
    }
  }
  return result;
}

/**
 * Creates a set object of `values`.
 *
 * @private
 * @param {Array} values The values to add to the set.
 * @returns {Object} Returns the new set.
 */
var createSet = !(Set && (1 / setToArray(new Set([,-0]))[1]) == INFINITY) ? noop : function(values) {
  return new Set(values);
};

/**
 * 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;
}

/**
 * Checks if `value` is a flattenable `arguments` object or array.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is flattenable, else `false`.
 */
function isFlattenable(value) {
  return isArray(value) || isArguments(value) ||
    !!(spreadableSymbol && value && value[spreadableSymbol]);
}

/**
 * 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);
}

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

/**
 * A specialized version of `baseRest` which transforms the rest array.
 *
 * @private
 * @param {Function} func The function to apply a rest parameter to.
 * @param {number} [start=func.length-1] The start position of the rest parameter.
 * @param {Function} transform The rest array transform.
 * @returns {Function} Returns the new function.
 */
function overRest(func, start, transform) {
  start = nativeMax(start === undefined ? (func.length - 1) : start, 0);
  return function() {
    var args = arguments,
        index = -1,
        length = nativeMax(args.length - start, 0),
        array = Array(length);

    while (++index < length) {
      array[index] = args[start + index];
    }
    index = -1;
    var otherArgs = Array(start + 1);
    while (++index < start) {
      otherArgs[index] = args[index];
    }
    otherArgs[start] = transform(array);
    return apply(func, this, otherArgs);
  };
}

/**
 * Sets the `toString` method of `func` to return `string`.
 *
 * @private
 * @param {Function} func The function to modify.
 * @param {Function} string The `toString` result.
 * @returns {Function} Returns `func`.
 */
var setToString = shortOut(baseSetToString);

/**
 * Creates a function that'll short out and invoke `identity` instead
 * of `func` when it's called `HOT_COUNT` or more times in `HOT_SPAN`
 * milliseconds.
 *
 * @private
 * @param {Function} func The function to restrict.
 * @returns {Function} Returns the new shortable function.
 */
function shortOut(func) {
  var count = 0,
      lastCalled = 0;

  return function() {
    var stamp = nativeNow(),
        remaining = HOT_SPAN - (stamp - lastCalled);

    lastCalled = stamp;
    if (remaining > 0) {
      if (++count >= HOT_COUNT) {
        return arguments[0];
      }
    } else {
      count = 0;
    }
    return func.apply(undefined, arguments);
  };
}

/**
 * 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 an array of unique values, in order, from all given arrays using
 * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
 * for equality comparisons.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Array
 * @param {...Array} [arrays] The arrays to inspect.
 * @returns {Array} Returns the new array of combined values.
 * @example
 *
 * _.union([2], [1, 2]);
 * // => [2, 1]
 */
var union = baseRest(function(arrays) {
  return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, 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
 */
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);
}

/**
 * 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 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';
}

/**
 * Creates a function that returns `value`.
 *
 * @static
 * @memberOf _
 * @since 2.4.0
 * @category Util
 * @param {*} value The value to return from the new function.
 * @returns {Function} Returns the new constant function.
 * @example
 *
 * var objects = _.times(2, _.constant({ 'a': 1 }));
 *
 * console.log(objects);
 * // => [{ 'a': 1 }, { 'a': 1 }]
 *
 * console.log(objects[0] === objects[1]);
 * // => true
 */
function constant(value) {
  return function() {
    return value;
  };
}

/**
 * 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;
}

/**
 * This method returns `undefined`.
 *
 * @static
 * @memberOf _
 * @since 2.3.0
 * @category Util
 * @example
 *
 * _.times(2, _.noop);
 * // => [undefined, undefined]
 */
function noop() {
  // No operation performed.
}

module.exports = union;