1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
var baseIndexOf = require('../internal/baseIndexOf'),
getLength = require('../internal/getLength'),
isArray = require('../lang/isArray'),
isIterateeCall = require('../internal/isIterateeCall'),
isLength = require('../internal/isLength'),
isString = require('../lang/isString'),
values = require('../object/values');
/* Native method references for those with the same name as other `lodash` methods. */
var nativeMax = Math.max;
/**
* Checks if `value` is in `collection` using
* [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for equality comparisons. If `fromIndex` is negative, it is used as the offset
* from the end of `collection`.
*
* @static
* @memberOf _
* @alias contains, include
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {*} target The value to search for.
* @param {number} [fromIndex=0] The index to search from.
* @param- {Object} [guard] Enables use as a callback for functions like `_.reduce`.
* @returns {boolean} Returns `true` if a matching element is found, else `false`.
* @example
*
* _.includes([1, 2, 3], 1);
* // => true
*
* _.includes([1, 2, 3], 1, 2);
* // => false
*
* _.includes({ 'user': 'fred', 'age': 40 }, 'fred');
* // => true
*
* _.includes('pebbles', 'eb');
* // => true
*/
function includes(collection, target, fromIndex, guard) {
var length = collection ? getLength(collection) : 0;
if (!isLength(length)) {
collection = values(collection);
length = collection.length;
}
if (!length) {
return false;
}
if (typeof fromIndex != 'number' || (guard && isIterateeCall(target, fromIndex, guard))) {
fromIndex = 0;
} else {
fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (fromIndex || 0);
}
return (typeof collection == 'string' || !isArray(collection) && isString(collection))
? (fromIndex < length && collection.indexOf(target, fromIndex) > -1)
: (baseIndexOf(collection, target, fromIndex) > -1);
}
module.exports = includes;
|
