And why do you care to iterate by code unit? I mean, sure it seems useful, but how useful?
Do you want to stop in the middle of Ä? You probably don't stop in the middle of Ä. I have no problem with regular expressions or APIs that use 32bit (well, 21bit) values, but I think existing apps already have a preconceived notion of the index in the string that it'd be bad to break. Yes that means += 2 instead of ++ to get past a surrogate pair, but that happens to Ä as well. -Shawn -----Original Message----- From: Mike Samuel [mailto:[email protected]] Sent: Monday, May 16, 2011 6:03 PM To: Shawn Steele Cc: Allen Wirfs-Brock; es-discuss Subject: Re: UTF-16 vs UTF-32 2011/5/16 Shawn Steele <[email protected]>: > It's clear why we want to support the full Unicode range, but it's less clear > to me why UTF-32 would be desirable internally. (Sure, it'd be nice for > conversion types). I don't think anyone says that UTF-32 is desirable *internally*. We're talking about the API of the string type. I have been operating under the assumption that developers would benefit from a simple way to efficiently iterate by code unit. An efficient version of the below, ideally one that just works like current for (var i = 0, n = str.length; i < n; ++i) ...str[i]... function iterateByCodeUnit(str, fn) { str += ''; for (var i = 0, n = str.length, index; i < n; ++i, ++index) { var unit = str.charCodeAt(i); if (0xd800 <= unit && unit < 0xdc00 && i + 1 < n) { var next = str.charCodeAt(i + 1); if (0xdc00 <= next && next < 0xe000) { fn(((unit & 0x3ff) << 10) | (next & 0x3ff), i, index); ++i; continue; } } fn(unit, i, index); } } _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
