22 lines
505 B
Markdown
22 lines
505 B
Markdown
---
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title: mapObject
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tags: array,object,intermediate
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---
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Maps the values of an array to an object using a function.
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- Use `Array.prototype.reduce()` to apply `fn` to each element in `arr` and combine the results into an object.
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- Use `el` as the key for each property and the result of `fn` as the value.
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```js
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const mapObject = (arr, fn) =>
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arr.reduce((acc, el, i) => {
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acc[el] = fn(el, i, arr);
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return acc;
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}, {});
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```
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```js
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mapObject([1, 2, 3], a => a * a); // { 1: 1, 2: 4, 3: 9 }
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```
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