10 lines
358 B
Markdown
10 lines
358 B
Markdown
### Array includes
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Use `slice()` to offset the array/string. `Array.indexOf()` returns `-1` if the sub-string/array dosen't contain the given `value`.
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```js
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const includes = (collection, val, fromIndex=0) => collection.slice(fromIndex).indexOf(val) != -1;
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// includes("30-seconds-of-code", "code") -> true
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// includes([1, 2, 3, 4], [1, 2], 1) -> false
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``` |