- From: Bert Bos <bert@w3.org>
- Date: Wed, 22 Apr 2009 15:43:14 +0200
- To: W3C Emailing list for WWW Style <www-style@w3.org>
On Tuesday 21 April 2009, Zack Weinberg wrote:
> Mozilla has a bug report[1] requesting that this:
>
> font-family: "lucida" grande;
>
> be treated as equivalent to this:
>
> font-family: lucida grande;
>
> There is no formal grammar for <family-name> and the prose does not
> say whether some-but-not-all tokens of a family-name can be quoted.
> Matter of fact, it doesn't really explain what the grammar is at all
> - it just says that certain punctuation characters must be \-escaped
> if they appear unquoted in a family-name.
>
> My preferred reading of the spec would disallow partial quotation,
> but what I really care about as an implementor is that there be an
> unambiguous, ideally formal, grammar for every nonterminal.
Partially quoted names were not among the original use cases. Maybe it's
possible to read the spec as syntactically allowing them, but it
certainly doesn't define what they mean.
The intent can, I think, be captured by this annotated grammar:
Value: [ [ <family-name> | <generic-family> ] [ , <family-name> |
<generic-family> ]* ] | inherit;
<generic-family>: serif | sans-serif | cursive | fantasy | monospace;
<family-name>: STRING | IDENT+; /* see restriction below */
where the restriction is that <family-name> cannot be one of the single
IDENTs serif, sans-serif, cursive, fantasy, monospace, inherit, default
or initial.
(The spec is not worded very well with respect to 'default'
and 'initial', implying that it is somehow obvious that they are
reserved, although it is only obvious if you've read CSS3 Values And
Units...)
>
> zw
>
> [1] https://bugzilla.mozilla.org/show_bug.cgi?id=481502 (note that
> the initial discussion is about font: rather than font-family:, but
> the requested change would affect both, and is easier to explain in
> terms of the longhand notation).
Bert
--
Bert Bos ( W 3 C ) http://www.w3.org/
http://www.w3.org/people/bos W3C/ERCIM
bert@w3.org 2004 Rt des Lucioles / BP 93
+33 (0)4 92 38 76 92 06902 Sophia Antipolis Cedex, France
Received on Wednesday, 22 April 2009 13:43:54 UTC