On Oct 18, 2013, at 10:53 PM, Domenic Denicola wrote:
> On 19 Oct 2013, at 01:12, "Mathias Bynens" <[email protected]> wrote:
>> `String.prototype.codePointAt` or `String.prototype.at` come in handy in
>> case you only need to get the first code point or symbol in a string, for
>> example.
>
> Are they useful for anything else, though? For example, if I wanted to get
> the second symbol in a string, how would I do that?
We discussed the utility of 'codePointAt' in the context of Norbert's full
Unicode support proposal. At that time we concluded that it was something we
needed. I don't see any new evidence that suggests that we need to reopen
that decision at this point in the process.
The utility of a hypothetical 'at' method is presumably exactly that of
'codePointAt'.
str.at(p)
would just be a convenience for expressing
String.fromCodePoint(str.codePointAt(p))
So the real question is probably, how common is that use case.
It's relatively easy using 'at' do a for loop over the characters of a string
using 'at'. Something like:
let c = '';
for (let p=0; p<str.length; p+=c.length) {
c = str.at(p);
...
}
although, a for-of would be better in most cases:
for (let c of str)
The use case that we don't support well is any sort of back wards iteration of
the characters of a string. We don't current have an iterator specified to do
it, nor do we have a one stop way to test whether we at looking at the trailing
surrogate of a surrogate pair.
Allen
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss
