| /** |
| * Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/> |
| * Build: `lodash modularize modern exports="node" -o ./modern/` |
| * Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/> |
| * Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE> |
| * Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors |
| * Available under MIT license <http://lodash.com/license> |
| */ |
| var baseIndexOf = require('../internals/baseIndexOf'), |
| forOwn = require('../objects/forOwn'), |
| isArray = require('../objects/isArray'), |
| isString = require('../objects/isString'); |
| |
| /* Native method shortcuts for methods with the same name as other `lodash` methods */ |
| var nativeMax = Math.max; |
| |
| /** |
| * Checks if a given value is present in a collection using strict equality |
| * for comparisons, i.e. `===`. If `fromIndex` is negative, it is used as the |
| * offset from the end of the collection. |
| * |
| * @static |
| * @memberOf _ |
| * @alias include |
| * @category Collections |
| * @param {Array|Object|string} collection The collection to iterate over. |
| * @param {*} target The value to check for. |
| * @param {number} [fromIndex=0] The index to search from. |
| * @returns {boolean} Returns `true` if the `target` element is found, else `false`. |
| * @example |
| * |
| * _.contains([1, 2, 3], 1); |
| * // => true |
| * |
| * _.contains([1, 2, 3], 1, 2); |
| * // => false |
| * |
| * _.contains({ 'name': 'fred', 'age': 40 }, 'fred'); |
| * // => true |
| * |
| * _.contains('pebbles', 'eb'); |
| * // => true |
| */ |
| function contains(collection, target, fromIndex) { |
| var index = -1, |
| indexOf = baseIndexOf, |
| length = collection ? collection.length : 0, |
| result = false; |
| |
| fromIndex = (fromIndex < 0 ? nativeMax(0, length + fromIndex) : fromIndex) || 0; |
| if (isArray(collection)) { |
| result = indexOf(collection, target, fromIndex) > -1; |
| } else if (typeof length == 'number') { |
| result = (isString(collection) ? collection.indexOf(target, fromIndex) : indexOf(collection, target, fromIndex)) > -1; |
| } else { |
| forOwn(collection, function(value) { |
| if (++index >= fromIndex) { |
| return !(result = value === target); |
| } |
| }); |
| } |
| return result; |
| } |
| |
| module.exports = contains; |