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Built-in-references

Built-in constructor / method / info / value / Mocked references.

// var runInContext = (function runInContext(context) {
    context = context == null ? root : _.defaults(root.Object(), context, _.pick(root, contextProps));

    /** Built-in constructor references. */
    var Array = context.Array,
        Date = context.Date,
        Error = context.Error,
        Function = context.Function,
        Math = context.Math,
        Object = context.Object,
        RegExp = context.RegExp,
        String = context.String,
        TypeError = context.TypeError;

    /** 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 = context['__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 generate unique IDs. */
    var idCounter = 0;

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

    /** Used to restore the original `_` reference in `_.noConflict`. */
    var oldDash = root._;

    /** 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 ? context.Buffer : undefined,
        Symbol = context.Symbol,
        Uint8Array = context.Uint8Array,
        allocUnsafe = Buffer ? Buffer.allocUnsafe : undefined,
        getPrototype = overArg(Object.getPrototypeOf, Object),
        objectCreate = Object.create,
        propertyIsEnumerable = objectProto.propertyIsEnumerable,
        splice = arrayProto.splice,
        spreadableSymbol = Symbol ? Symbol.isConcatSpreadable : undefined,
        symIterator = Symbol ? Symbol.iterator : undefined,
        symToStringTag = Symbol ? Symbol.toStringTag : undefined;

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

    /** Mocked built-ins. */
    var ctxClearTimeout = context.clearTimeout !== root.clearTimeout && context.clearTimeout,
        ctxNow = Date && Date.now !== root.Date.now && Date.now,
        ctxSetTimeout = context.setTimeout !== root.setTimeout && context.setTimeout;

    /* Built-in method references for those with the same name as other `lodash` methods. */
    var nativeCeil = Math.ceil,
        nativeFloor = Math.floor,
        nativeGetSymbols = Object.getOwnPropertySymbols,
        nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined,
        nativeIsFinite = context.isFinite,
        nativeJoin = arrayProto.join,
        nativeKeys = overArg(Object.keys, Object),
        nativeMax = Math.max,
        nativeMin = Math.min,
        nativeNow = Date.now,
        nativeParseInt = context.parseInt,
        nativeRandom = Math.random,
        nativeReverse = arrayProto.reverse;

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

    /** Used to store function metadata. */
    var metaMap = WeakMap && new WeakMap;

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

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

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

// ......