`Array.prototype.nth(n=0)` looks great indeed, +1 here About the Symbol ... ugly as hell also we need to write even more and it doesn't scale as utility compared to .nth
```js a[Symbol.last] a[a.length-1] ``` I mean, seriously ... don't even consider that or someone might ask to implement `Symbol.first` with second, third and all others too ... how about `Symbol.odd` /sarcasm Best Regards On Sat, Jan 23, 2016 at 8:56 PM, Michał Wadas <[email protected]> wrote: > I can't consider `.last(1)` method to be readable... > But I think `.nth(n)` method with support for negative index would be > really useful. > > 2016-01-23 17:32 GMT+01:00 kdex <[email protected]>: > >> Not every feature addition is due to performance or paradigms. Just have a >> look at ES2015: I'm sure that this has neither been the motivation for >> `String.prototype.startsWith`nor for `String.prototype.includes`. Even >> `String.prototype.repeat` appears so simple that a loop paired with a >> concatenation could have become a popular alternative. >> >> Of course you could solve most of these string problems with earlier >> versions >> of the language, too, often explicitly thinking with incides. But on the >> downside, your code suddenly becomes a potentially unintuitive, >> index-ridden >> mess, introducing off-by-one and out-of-bound errors (it even happened to >> someone on this thread, too, if you review Thomas' code from above). This >> isn't really all too much about saving keystrokes, but mainly about >> writing >> clean, readable and maintainable code. >> >> There's array::back in C++, negative indices in Python as well as Bash or >> end >> in PHP, so I don't see any reason why we should complicate things for >> people >> coming from these languages. Nor to I see why we should torture ourselves >> thinking about how the underlying data structure stores its elements >> internally when all I care about is reading the last element. >> >> Just ask yourself: Do you think it's substantially more readable to write >> >> ```js >> [1, 2, 3].slice(-2)[1]; >> ``` >> over >> ``` >> [1, 2, 3].last(1); >> ``` >> ? >> >> If it comes to write access, I agree that`Symbol.last` could be another >> handy >> addition (it doesn't have to be an "either/or" discussion, really): >> >> [1, 2, 3][Symbol.last]; // 3 >> [1, 2, 3][Symbol.last] = 4; // 4 >> [1, 2, 3].last(1); // 2 >> >> On Samstag, 23. Januar 2016 18:01:24 CET Bob Myers wrote: >> > On Sat, Jan 23, 2016 at 12:54 PM, kdex <[email protected]> wrote: >> > > [1, 2, 3].last(); // 3 >> > >> > I'm wondering what the ultimate motivation for suggestions like this >> is. Is >> > it to save key strokes? Allow more semantic coding? Support new >> paradigms? >> > Performance? 'm sure someone has already come up with a good >> categorization >> > like this, would someone mind providing a link? Could one of these be >> > considered the "theme" for the next version? >> > >> > I have to admit to be being quite negative about proposals of the form >> > "Hey, this other language does X, can we do that too?", or "It would be >> so >> > cool if we could do Y", especially when these are mostly about syntax. >> Is a >> > missing `last` really one of our painpoints? >> > >> > Bob >> >> _______________________________________________ >> es-discuss mailing list >> [email protected] >> https://mail.mozilla.org/listinfo/es-discuss >> > > > _______________________________________________ > es-discuss mailing list > [email protected] > https://mail.mozilla.org/listinfo/es-discuss > >
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