21 lines
555 B
Markdown
21 lines
555 B
Markdown
---
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title: takeWhile
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tags: array,intermediate
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---
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Removes elements in an array until the passed function returns `true`. Returns the removed elements.
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- Loop through the array, using a `for...of` loop over `Array.prototype.entries()` until the returned value from the function is `true`.
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- Return the removed elements, using `Array.prototype.slice()`.
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```js
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const takeWhile = (arr, func) => {
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for (const [i, val] of arr.entries()) if (func(val)) return arr.slice(0, i);
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return arr;
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};
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```
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```js
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takeWhile([1, 2, 3, 4], n => n >= 3); // [1, 2]
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```
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