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Simplify countBy

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Siarhei
2018-10-15 12:18:24 +04:00
parent fd927950a8
commit 782192943a
2 changed files with 2 additions and 2 deletions
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2
snippets/countBy.md
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@ -7,7 +7,7 @@ Use `Array.prototype.reduce()` to create an object, where the keys are produced
```js ```js
const countBy = (arr, fn) => const countBy = (arr, fn) =>
arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val, i) => { arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val) => {
acc[val] = (acc[val] || 0) + 1; acc[val] = (acc[val] || 0) + 1;
return acc; return acc;
}, {}); }, {});

2
test/countBy/countBy.js
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@ -1,5 +1,5 @@
const countBy = (arr, fn) => const countBy = (arr, fn) =>
arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val, i) => { arr.map(typeof fn === 'function' ? fn : val => val[fn]).reduce((acc, val) => {
acc[val] = (acc[val] || 0) + 1; acc[val] = (acc[val] || 0) + 1;
return acc; return acc;
}, {}); }, {});