在 2016/9/28 14:42, Claude Pache 写道:
Le 28 sept. 2016 à 07:38, 段垚 <duan...@ustc.edu
<mailto:duan...@ustc.edu>> a écrit :
Because `foo.bar` is equivlant to `foo['bar']` in JS so far, and
`array.-1` could break this consistency.
On the other hand, `array.first()` seems not necessary because
`array[0]` is even more handy; `array.last()` looks fine to me.
If someone prefer a more general solution, I recommand `array.get(n)`:
* if n >= 0 && n < array.length: equivlant to array[n]
* if n < 0 && -n < array.length: equivlant to array[array.length + n]
* if n <= -array.length || n >= array.length: throw or return undefined
* if n is not a integer or not a number: throw or return undefined
The last 2 rules make `array.get(n)` less error prone than
`array[n]`. I prefer throwing, but maybe returning undefined is more
JS-style?
For consistency with the rest of the builtin library, `array.get(n)`
should be equivalent to `array.slice(n)[0]`, which means: convert `n`
to an integer, and: return `undefined` for out-of-bound index.
I regard such converting behavior a bad legacy of JS, and want to avoid
it in new APIs.
—Claude
_______________________________________________
es-discuss mailing list
es-discuss@mozilla.org
https://mail.mozilla.org/listinfo/es-discuss
