Was this supposed to be on the list? I'm not sure, so I'll reply to
you personally. Feel free to forward it if you want.
Le 2007-05-17 à 16:44, Adrienne Travis a écrit :
The CSS 1 spec says that a selector CANNOT start with a dash. I find
nothing in the CSS 2 spec to overwrite that, though i could be missing
something.
"in CSS1, selectors (element names, classes and IDs) can contain only
the characters A-Z, 0-9, and Unicode characters 161-255, plus dash
(-); they cannot start with a dash or a digit; they can also contain
escaped characters and any Unicode character as a numeric code (see
next item)."
Again, hard to say if it's important to have backwards-compatibility
or not, but that IS an issue.
Possibly not much of an issue however since browsers following the
specification would have to handle it anyway, if they follow the
normative grammar of the language.
With CSS 3, the grammar of the class selector is defined this way:
class
: '.' IDENT
;
In other words: a dot followed by IDENT, with IDENT defined as:
ident [-]?{nmstart}{nmchar}*
Which is: an optional dash, a start character (alphabetic +
underscore + extended unicode) followed by any character
(alphanumeric + underscore + dash + extended unicode).
In other word, a class name may not begin with a number, but, per CSS
3, it can begin with a dash. I found no other paragraph disallowing
class name selectors starting with a dash.
-- CSS 3 grammar: http://www.w3.org/TR/2005/WD-css3-
selectors-20051215/#w3cselgrammar
CSS 2.1 allows the leading dash just like CSS 3, but surprisingly
does not allow any (non-escaped) underscore in a class name.
-- CSS 2.1 grammar: http://www.w3.org/TR/CSS21/grammar.html
CSS 2 grammar does not allow the leading dash.
-- CSS 2 grammar: http://www.w3.org/TR/REC-CSS2/grammar.html
Following the formal grammar of CSS 1 is a little more complicated,
but it seems that the leading dash is allowed by the grammar, even if
disallowed by the text in the specification. (CLASS defined as
"."{name} with NAME being {nmchar}+ and NMCHAR including the dash.)
-- CSS 1 grammar: http://www.w3.org/TR/REC-CSS1#appendix-b
Michel Fortin
[EMAIL PROTECTED]
http://www.michelf.com/
