@pactsafe/pactsafe-react-sdk/umd/pactsafe-react-sdk.js

Ironclad Clickwrap React SDK - SDK for easy Ironclad Clickwrap implementations leveraging the Ironclad JavaScript Library & API

/*!
 * @pactsafe/pactsafe-react-sdk v2.15.0 - https://github.com/PactSafe/pactsafe-react-sdk
 * MIT Licensed
 */
(function webpackUniversalModuleDefinition(root, factory) {
	if(typeof exports === 'object' && typeof module === 'object')
		module.exports = factory(require("react"));
	else if(typeof define === 'function' && define.amd)
		define(["react"], factory);
	else if(typeof exports === 'object')
		exports["PSReactSDK"] = factory(require("react"));
	else
		root["PSReactSDK"] = factory(root["React"]);
})(window, function(__WEBPACK_EXTERNAL_MODULE__2__) {
return /******/ (function(modules) { // webpackBootstrap
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/******/ 			i: moduleId,
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/******/ 		module.l = true;
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/* 0 */
/***/ (function(module, exports, __webpack_require__) {

/**
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

if (false) { var throwOnDirectAccess, ReactIs; } else {
  // By explicitly using `prop-types` you are opting into new production behavior.
  // http://fb.me/prop-types-in-prod
  module.exports = __webpack_require__(8)();
}


/***/ }),
/* 1 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";
Object.defineProperty(exports,'__esModule',{value:!0});var VALIDATOR_ARG_ERROR_MESSAGE='The typeValidator argument must be a function with the signature function(props, propName, componentName).',MESSAGE_ARG_ERROR_MESSAGE='The error message is optional, but must be a string if provided.',propIsRequired=function propIsRequired(a,b,c,d){if('boolean'==typeof a)return a;return'function'==typeof a?a(b,c,d):!(!0!==!!a)&&!!a},propExists=function propExists(a,b){return Object.hasOwnProperty.call(a,b)},missingPropError=function missingPropError(a,b,c,d){return d?new Error(d):new Error('Required '+a[b]+' `'+b+'`'+(' was not specified in `'+c+'`.'))},guardAgainstInvalidArgTypes=function guardAgainstInvalidArgTypes(a,b){if('function'!=typeof a)throw new TypeError(VALIDATOR_ARG_ERROR_MESSAGE);if(!!b&&'string'!=typeof b)throw new TypeError(MESSAGE_ARG_ERROR_MESSAGE)},isRequiredIf=function isRequiredIf(a,b,c){return guardAgainstInvalidArgTypes(a,c),function(d,e,f){for(var _len=arguments.length,g=Array(3<_len?_len-3:0),_key=3;_key<_len;_key++)g[_key-3]=arguments[_key];return propIsRequired(b,d,e,f)?propExists(d,e)?a.apply(void 0,[d,e,f].concat(g)):missingPropError(d,e,f,c):a.apply(void 0,[d,e,f].concat(g));// Is not required, so just run typeValidator.
}};exports.default=isRequiredIf;

//# sourceMappingURL=isRequiredIf.js.map

/***/ }),
/* 2 */
/***/ (function(module, exports) {

module.exports = __WEBPACK_EXTERNAL_MODULE__2__;

/***/ }),
/* 3 */
/***/ (function(module, exports) {

/*
 * This file is used to share the snippet injection code between PSClickWrap.js and PSBrowseWrap.js. It is mostly the same as the existing snippet code, only exception is the
 * PS.JS source location is paramaterized.
 */

function injectSnippet(scriptURL, backupScriptURL) {
  (function (w, d, s, c, f, n, t, g, a, b, l) {
    // Defines the global _ps object and initializes the _ps() function
    // that will queue commands until the PactSafe Library is ready.
    w.PactSafeObject = n;
    w[n] = w[n] || function () {
      (w[n].q = w[n].q || []).push(arguments);
    }, w[n].on = function () {
      // Defines the event functions for the global _ps object.
      (w[n].e = w[n].e || []).push(arguments);
    }, w[n].once = function () {
      (w[n].eo = w[n].eo || []).push(arguments);
    }, w[n].off = function () {
      (w[n].o = w[n].o || []).push(arguments);
    }, w[n].t = 1 * new Date(), w[n].l = 0; // Marks the time that the script is inserted.

    // Inserts a new script element to load the PactSafe Library JS file (ps.js).
    a = d.createElement(s);
    b = d.getElementsByTagName(s)[0];
    a.async = 1;
    a.src = c;

    // Marks that the script has started loading or failed to load.
    a.onload = a.onreadystatechange = function () {
      w[n].l = 1;
    };
    a.onerror = a.onabort = function () {
      w[n].l = 0;
    };

    // Insert the script tag to the DOM, n a testing context, no script tags exist so b is undefined.
    if (b) {
      b.parentNode.insertBefore(a, b);
    } else {
      document.body.appendChild(a);
    }

    // Retry loading the script from a fallback location after 4 seconds.
    setTimeout(function () {
      if (!w[n].l && !w[n].loaded) {
        w[n].error = 1;
        a = d.createElement(s);
        a.async = 1;
        a.src = f;
        a.onload = a.onreadystatechange = function () {
          w[n].l = 1;
        };
        a.onerror = a.onabort = function () {
          w[n].l = 0;
        };
        b.parentNode.insertBefore(a, b);

        // Log the loading error via beacon.
        l = function l(u, e) {
          try {
            e = d.createElement("img");
            e.src = "https://d3r8bdci515tjv.cloudfront.net/error.gif?t=" + w[n].t + "&u=" + encodeURIComponent(u);
            d.getElementsByTagName("body")[0].appendChild(e);
          } catch (x) {}
        };
        l(c);

        // Call the optional error callback function after a second failed attempt.
        setTimeout(function () {
          if (!w[n].l && !w[n].loaded) {
            w[n].error = 1;
            if (g && "function" == typeof g) {
              g.call(this);
            }
            l(f);
          }
        }, t);
      }
    }, t);
  })(window, document, "script", scriptURL, backupScriptURL, "_ps", 4000, function optionalErrorCallback() {
    console.log("Unable to load the PactSafe PS.JS Library.");
  });
}
function isSnippetLoaded(psScriptURL) {
  var scripts = document.getElementsByTagName('script');
  if (window._ps && window._ps.loaded && window._ps.realThang === 317) return true;
  for (var i = 0; i < scripts.length; i += 1) {
    if (scripts[i].src && scripts[i].src.indexOf(psScriptURL) !== -1) {
      return true;
    }
  }
  return false;
}
module.exports = {
  injectSnippet: injectSnippet,
  isSnippetLoaded: isSnippetLoaded
};

/***/ }),
/* 4 */
/***/ (function(module, exports, __webpack_require__) {

/* WEBPACK VAR INJECTION */(function(global, module) {/**
 * Lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * 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
 */

/** 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 value comparisons. */
var COMPARE_PARTIAL_FLAG = 1,
    COMPARE_UNORDERED_FLAG = 2;

/** 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 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;

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

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

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

/** Detect free variable `exports`. */
var freeExports =  true && 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 nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;

/**
 * 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;
}

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

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

/**
 * 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);
  };
}

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

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

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

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

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

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

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

/** Used to 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,
    propertyIsEnumerable = objectProto.propertyIsEnumerable,
    splice = arrayProto.splice,
    symToStringTag = Symbol ? Symbol.toStringTag : undefined;

/* 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 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 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;

/**
 * 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;
}

/**
 * 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 `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 `_.isEqual` which supports partial comparisons
 * and tracks traversed objects.
 *
 * @private
 * @param {*} value The value to compare.
 * @param {*} other The other value to compare.
 * @param {boolean} bitmask The bitmask flags.
 *  1 - Unordered comparison
 *  2 - Partial comparison
 * @param {Function} [customizer] The function to customize comparisons.
 * @param {Object} [stack] Tracks traversed `value` and `other` objects.
 * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
 */
function baseIsEqual(value, other, bitmask, customizer, stack) {
  if (value === other) {
    return true;
  }
  if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) {
    return value !== value && other !== other;
  }
  return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack);
}

/**
 * A specialized version of `baseIsEqual` for arrays and objects which performs
 * deep comparisons and tracks traversed objects enabling objects with circular
 * references to be compared.
 *
 * @private
 * @param {Object} object The object to compare.
 * @param {Object} other The other object to compare.
 * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
 * @param {Function} customizer The function to customize comparisons.
 * @param {Function} equalFunc The function to determine equivalents of values.
 * @param {Object} [stack] Tracks traversed `object` and `other` objects.
 * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
 */
function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
  var objIsArr = isArray(object),
      othIsArr = isArray(other),
      objTag = objIsArr ? arrayTag : getTag(object),
      othTag = othIsArr ? arrayTag : getTag(other);

  objTag = objTag == argsTag ? objectTag : objTag;
  othTag = othTag == argsTag ? objectTag : othTag;

  var objIsObj = objTag == objectTag,
      othIsObj = othTag == objectTag,
      isSameTag = objTag == othTag;

  if (isSameTag && isBuffer(object)) {
    if (!isBuffer(other)) {
      return false;
    }
    objIsArr = true;
    objIsObj = false;
  }
  if (isSameTag && !objIsObj) {
    stack || (stack = new Stack);
    return (objIsArr || isTypedArray(object))
      ? equalArrays(object, other, bitmask, customizer, equalFunc, stack)
      : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack);
  }
  if (!(bitmask & COMPARE_PARTIAL_FLAG)) {
    var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
        othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');

    if (objIsWrapped || othIsWrapped) {
      var objUnwrapped = objIsWrapped ? object.value() : object,
          othUnwrapped = othIsWrapped ? other.value() : other;

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

/**
 * 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 `_.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;
}

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

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

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

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

    if (customizer) {
      var compared = isPartial
        ? customizer(othValue, arrValue, index, other, array, stack)
        : customizer(arrValue, othValue, index, array, other, stack);
    }
    if (compared !== undefined) {
      if (compared) {
        continue;
      }
      result = false;
      break;
    }
    // Recursively compare arrays (susceptible to call stack limits).
    if (seen) {
      if (!arraySome(other, function(othValue, othIndex) {
            if (!cacheHas(seen, othIndex) &&
                (arrValue === othValue || equalFunc(arrValue, othValue, bitmask, customizer, stack))) {
              return seen.push(othIndex);
            }
          })) {
        result = false;
        break;
      }
    } else if (!(
          arrValue === othValue ||
            equalFunc(arrValue, othValue, bitmask, customizer, stack)
        )) {
      result = false;
      break;
    }
  }
  stack['delete'](array);
  stack['delete'](other);
  return result;
}

/**
 * A specialized version of `baseIsEqualDeep` for comparing objects of
 * the same `toStringTag`.
 *
 * **Note:** This function only supports comparing values with tags of
 * `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
 *
 * @private
 * @param {Object} object The object to compare.
 * @param {Object} other The other object to compare.
 * @param {string} tag The `toStringTag` of the objects to compare.
 * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
 * @param {Function} customizer The function to customize comparisons.
 * @param {Function} equalFunc The function to determine equivalents of values.
 * @param {Object} stack Tracks traversed `object` and `other` objects.
 * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
 */
function equalByTag(object, other, tag, bitmask, customizer, equalFunc, stack) {
  switch (tag) {
    case dataViewTag:
      if ((object.byteLength != other.byteLength) ||
          (object.byteOffset != other.byteOffset)) {
        return false;
      }
      object = object.buffer;
      other = other.buffer;

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

    case boolTag:
    case dateTag:
    case numberTag:
      // Coerce booleans to `1` or `0` and dates to milliseconds.
      // Invalid dates are coerced to `NaN`.
      return eq(+object, +other);

    case errorTag:
      return object.name == other.name && object.message == other.message;

    case regexpTag:
    case stringTag:
      // Coerce regexes to strings and treat strings, primitives and objects,
      // as equal. See http://www.ecma-international.org/ecma-262/7.0/#sec-regexp.prototype.tostring
      // for more details.
      return object == (other + '');

    case mapTag:
      var convert = mapToArray;

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

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

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

    case symbolTag:
      if (symbolValueOf) {
        return symbolValueOf.call(object) == symbolValueOf.call(other);
      }
  }
  return false;
}

/**
 * A specialized version of `baseIsEqualDeep` for objects with support for
 * partial deep comparisons.
 *
 * @private
 * @param {Object} object The object to compare.
 * @param {Object} other The other object to compare.
 * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
 * @param {Function} customizer The function to customize comparisons.
 * @param {Function} equalFunc The function to determine equivalents of values.
 * @param {Object} stack Tracks traversed `object` and `other` objects.
 * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
 */
function equalObjects(object, other, bitmask, customizer, equalFunc, stack) {
  var isPartial = bitmask & COMPARE_PARTIAL_FLAG,
      objProps = getAllKeys(object),
      objLength = objProps.length,
      othProps = getAllKeys(other),
      othLength = othProps.length;

  if (objLength != othLength && !isPartial) {
    return false;
  }
  var index = objLength;
  while (index--) {
    var key = objProps[index];
    if (!(isPartial ? key in other : hasOwnProperty.call(other, key))) {
      return false;
    }
  }
  // Assume cyclic values are equal.
  var stacked = stack.get(object);
  if (stacked && stack.get(other)) {
    return stacked == other;
  }
  var result = true;
  stack.set(object, other);
  stack.set(other, object);

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

    if (customizer) {
      var compared = isPartial
        ? customizer(othValue, objValue, key, other, object, stack)
        : customizer(objValue, othValue, key, object, other, stack);
    }
    // Recursively compare objects (susceptible to call stack limits).
    if (!(compared === undefined
          ? (objValue === othValue || equalFunc(objValue, othValue, bitmask, customizer, stack))
          : compared
        )) {
      result = false;
      break;
    }
    skipCtor || (skipCtor = key == 'constructor');
  }
  if (result && !skipCtor) {
    var objCtor = object.constructor,
        othCtor = other.constructor;

    // Non `Object` object instances with different constructors are not equal.
    if (objCtor != othCtor &&
        ('constructor' in object && 'constructor' in other) &&
        !(typeof objCtor == 'function' && objCtor instanceof objCtor &&
          typeof othCtor == 'function' && othCtor instanceof othCtor)) {
      result = false;
    }
  }
  stack['delete'](object);
  stack['delete'](other);
  return result;
}

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

/**
 * Gets the 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);
  });
};

/**
 * 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;
  };
}

/**
 * Checks if `value` is a valid array-like index.
 *
 * @private
 * @param {*} value The value to check.
 * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
 * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
 */
function isIndex(value, length) {
  length = length == null ? MAX_SAFE_INTEGER : length;
  return !!length &&
    (typeof value == 'number' || reIsUint.test(value)) &&
    (value > -1 && value % 1 == 0 && value < length);
}

/**
 * Checks if `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 protot