Proposal: Array.prototype.count

Jordan Harband ljharb at gmail.com
Mon Jan 7 19:29:32 UTC 2019


All the iteration methods are a specific case of reduce, in that you can
implement them all with reduce.

On Mon, Jan 7, 2019 at 11:27 AM Ranando King <kingmph at gmail.com> wrote:

> Isn't that just a specific case of Array.prototype.reduce?
>
> ```js
> const evenNumberCount = [1,2,3,4,5].reduce((acc, val) => { !(val % 2)
> && ++acc; });
> ```
>
> On Mon, Jan 7, 2019 at 1:12 PM Засим Александр <al.zasim at gmail.com> wrote:
>
>> Hi everyone. This is proposal for Array.prototype.count (or countOf)
>> method which allow to count specific elements in an array.
>>
>> ```js
>>
>> const evenNumberCount = [1, 2, 3, 4, 5].count(num => num % 2 === 0);
>>
>> ```
>>
>> Instead of
>>
>> ```js
>>
>> const evenNumberCount = [1, 2, 3, 4, 5].filter(num => num % 2 ===
>> 0).length;
>>
>> ```
>> _______________________________________________
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>>
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