Counting utf-8 characters -special characters

[majna]

I have character counter for textarea wich counting the characters.
Special character needs same place as two normal characters because of
16-bit encoding.
Counter is counting -2 when special character is added like some
language specific char.

How to count specials like 1 char?
tnx

[Thomas 'PointedEars' Lahn]

Thomas 'PointedEars' Lahn wrote:

majna wrote:

>I have character counter for textarea wich counting the characters.
Special character needs same place as two normal characters because of
16-bit encoding.

It doesn't.

>Counter is counting -2 when special character is added like some
language specific char.

Should have been -1. But even if most implementations would not be
UTF-16 safe, that would not have sufficed. UTF-16 does not mean that
the representation of a glyph in that encoding requires always only
16 bits:

http://www.unicode.org/faq/utf_bom.html#6

"€".length === 1

Windows(-1252). Hmpf. Make that "€" any Unicode glyph (such as "â‚*")
and it is still true.
PointedEars
--
var bugRiddenCrashPronePieceOfJunk = (
navigator.userAgent.indexOf('MSIE 5') != -1
&& navigator.userAgent.indexOf('Mac') != -1
) // Plone, register_function.js:16

[Johannes Baagoe]

Thomas 'PointedEars' Lahn :

"€".length === 1

Should be, since '€' (U+20AC) is represented as a single UTF-16 code
point, but it is not, e.g., in spidermonkey, which obviously uses UTF-8:

jse = "€"
€
jse.length
3
jsfor (i = 0; i < e.length; i++) {print(e.charCodeAt(i).toString(16))}
e2
82
ac

But then, OP mentions UTF-8 in the subject line.

>How to count specials like 1 char?

The same way. ECMAScript 3 implementations use UTF-16 encoded strings.
RTFM.

Hmmm. Is there *any* implementation that actually respects the requirement
of UTF-16?

Besides, even assuming UTF-16, some "language specific" characters (whatever
that means...) take up more than one code point. Some characters may even
use one or more code points according to whether one uses decomposition
or not, e.g., 'é' is either U+00E9 or U+0065 U+0301.

Short of testing each successive octet (if the implementation uses UTF-8)
or code point (if the implementation is correct according to the specs)
to see what kind of character it is, I have so far been unable to answer
the OP's question.

--
Johannes
"Quand on dit c'est un Johannes, cela vaut autant que ce que maintenant
on appelle un pédant" (H. Estienne, in É. Littré, /Dictionnaire de la
langue française/, art. PÉDANT)

[Johannes Baagoe]

Thomas 'PointedEars' Lahn :

[My version of SpiderMonkey uses UTF-8]

Probably due to your SpiderMonkey build. It works just fine since
Mozilla/4.0.

It does indeed in my version of Firefox. Serves me right for sticking with
obsolete command-line tools :-) It would appear that if I want a good
stand-alone ECMAScript interpreter, I have to compile it myself.

http://www.unicode.org/faq/char_combmark.html#2

Excellent, thanks a lot.

--
Johannes
"Quand on dit c'est un Johannes, cela vaut autant que ce que maintenant
on appelle un pédant" (H. Estienne, in É. Littré, /Dictionnaire de la
langue française/, art. PÉDANT)