mirror of
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114 lines
2.8 KiB
JavaScript
114 lines
2.8 KiB
JavaScript
/**
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* lodash 3.0.1 (Custom Build) <https://lodash.com/>
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* Build: `lodash modern modularize exports="npm" -o ./`
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* Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
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* Based on Underscore.js 1.8.2 <http://underscorejs.org/LICENSE>
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* Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
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* Available under MIT license <https://lodash.com/license>
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*/
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var isNative = require('lodash.isnative');
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/** Native method references. */
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var Set = isNative(Set = global.Set) && Set;
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/* Native method references for those with the same name as other `lodash` methods. */
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var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate;
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/**
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*
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* Creates a cache object to store unique values.
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*
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* @private
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* @param {Array} [values] The values to cache.
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*/
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function SetCache(values) {
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var length = values ? values.length : 0;
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this.data = { 'hash': nativeCreate(null), 'set': new Set };
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while (length--) {
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this.push(values[length]);
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}
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}
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/**
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* Adds `value` to the cache.
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*
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* @private
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* @name push
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* @memberOf SetCache
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* @param {*} value The value to cache.
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*/
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function cachePush(value) {
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var data = this.data;
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if (typeof value == 'string' || isObject(value)) {
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data.set.add(value);
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} else {
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data.hash[value] = true;
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}
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}
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/**
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* Creates a `Set` cache object to optimize linear searches of large arrays.
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*
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* @private
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* @param {Array} [values] The values to cache.
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* @returns {null|Object} Returns the new cache object if `Set` is supported, else `null`.
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*/
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var createCache = !(nativeCreate && Set) ? constant(null) : function(values) {
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return new SetCache(values);
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};
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/**
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* Checks if `value` is the [language type](https://es5.github.io/#x8) of `Object`.
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* (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
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*
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* @static
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* @memberOf _
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* @category Lang
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* @param {*} value The value to check.
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* @returns {boolean} Returns `true` if `value` is an object, else `false`.
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* @example
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*
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* _.isObject({});
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* // => true
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*
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* _.isObject([1, 2, 3]);
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* // => true
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*
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* _.isObject(1);
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* // => false
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*/
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function isObject(value) {
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// Avoid a V8 JIT bug in Chrome 19-20.
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// See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
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var type = typeof value;
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return type == 'function' || (!!value && type == 'object');
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}
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/**
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* Creates a function that returns `value`.
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*
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* @static
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* @memberOf _
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* @category Utility
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* @param {*} value The value to return from the new function.
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* @returns {Function} Returns the new function.
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* @example
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*
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* var object = { 'user': 'fred' };
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* var getter = _.constant(object);
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*
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* getter() === object;
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* // => true
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*/
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function constant(value) {
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return function() {
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return value;
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};
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}
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// Add functions to the `Set` cache.
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SetCache.prototype.push = cachePush;
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module.exports = createCache;
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