| var baseIndexOf = require('./_baseIndexOf'), |
| isArrayLike = require('./isArrayLike'), |
| isString = require('./isString'), |
| toInteger = require('./toInteger'), |
| values = require('./values'); |
| |
| /* Built-in method references for those with the same name as other `lodash` methods. */ |
| var nativeMax = Math.max; |
| |
| /** |
| * Checks if `value` is in `collection`. If `collection` is a string, it's |
| * checked for a substring of `value`, otherwise |
| * [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero) |
| * is used for equality comparisons. If `fromIndex` is negative, it's used as |
| * the offset from the end of `collection`. |
| * |
| * @static |
| * @memberOf _ |
| * @since 0.1.0 |
| * @category Collection |
| * @param {Array|Object|string} collection The collection to inspect. |
| * @param {*} value The value to search for. |
| * @param {number} [fromIndex=0] The index to search from. |
| * @param- {Object} [guard] Enables use as an iteratee for methods like `_.reduce`. |
| * @returns {boolean} Returns `true` if `value` is found, else `false`. |
| * @example |
| * |
| * _.includes([1, 2, 3], 1); |
| * // => true |
| * |
| * _.includes([1, 2, 3], 1, 2); |
| * // => false |
| * |
| * _.includes({ 'a': 1, 'b': 2 }, 1); |
| * // => true |
| * |
| * _.includes('abcd', 'bc'); |
| * // => true |
| */ |
| function includes(collection, value, fromIndex, guard) { |
| collection = isArrayLike(collection) ? collection : values(collection); |
| fromIndex = (fromIndex && !guard) ? toInteger(fromIndex) : 0; |
| |
| var length = collection.length; |
| if (fromIndex < 0) { |
| fromIndex = nativeMax(length + fromIndex, 0); |
| } |
| return isString(collection) |
| ? (fromIndex <= length && collection.indexOf(value, fromIndex) > -1) |
| : (!!length && baseIndexOf(collection, value, fromIndex) > -1); |
| } |
| |
| module.exports = includes; |