Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
15 lines
526 B
Markdown
15 lines
526 B
Markdown
### reduceSuccessive
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Applies a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values.
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Use `Array.prototype.reduce()` to apply the given function to the given array, storing each new result.
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```js
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const reduceSuccessive = (arr, fn, acc) =>
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arr.reduce((res, val, i, arr) => (res.push(fn(res.slice(-1)[0], val, i, arr)), res), [acc]);
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```
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```js
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reduceSuccessive([1, 2, 3, 4, 5, 6], (acc, val) => acc + val, 0); // [0, 1, 3, 6, 10, 15, 21]
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```
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