On Thu, May 17, 2018 at 11:16 AM, Ben Fletcher <[email protected]> wrote:
> Consider adding the array .map() implementation directly to the String > prototype. There is a big difference between mapping over an array and mapping over a string. Arrays can hold *anything*. Strings hold only characters. So for a function that takes something of type A and returns something of type B, `map`ping it over an array takes an array of As and returns an array of Bs. ```js ['a', 'b', 'c'].map(c => c.charCodeAt(0)) //=> [97, 98, 99] ``` But since a String only holds characters, we can't make it properly hold the results of `c => c.charCodeAt(0)`: ```js 'abc'.map(c => c.charCodeAt(0)) //=> "979899" ``` `reduce` would be a bit different, as it can accumulate to any type. I think `map` would be a bad idea here. -- Scott _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
