W3C home > Mailing lists > Public > www-style@w3.org > March 2012

Re: [css3-font] unquoted font family names with whitespace

From: John Daggett <jdaggett@mozilla.com>
Date: Fri, 16 Mar 2012 20:09:55 -0700 (PDT)
To: Simon Pieters <simonp@opera.com>
Cc: www-style@w3.org
Message-ID: <326999537.12759779.1331953795217.JavaMail.root@zimbra1.shared.sjc1.mozilla.com>
Simon Pieters wrote:

> "To avoid mistakes in escaping, it is recommended to quote font
> family names that contain white space, digits, or punctuation
> characters other than hyphens:"
> 
> http://dev.w3.org/csswg/css3-fonts/#propdef-font-family
> http://www.w3.org/TR/CSS21/fonts.html#font-family-prop
> 
> What mistake in escaping can one do when a font family name contains
> whitespace? Whitespace doesn't need escaping (unless a font has
> something funny like a tab character or two subsequent spaces, but
> such fonts don't exist). Unquoted font family names with spaces work
> fine. Don't recommend quoting them.
> 
> Unescaped unquoted font family names that start with a digit or
> contain punctuation characters other than hyphen will break *even if
> there is no whitespace*.

Unquoted family names must be sequences of CSS identifiers, in both
CSS 2.1 and CSS3 Fonts.  So you're right, family names don't need to
be quoted but I still think recommending quotes is a good rule of
thumb, it avoids authors needing to understand precisely what is and
isn't a "sequence of CSS identifiers" (the spec does show several
examples of invalid names).  The email interchange problem with
Outlook 2007 is unfortunate but I don't see a reason to update the
wording because of bugs in legacy versions of software.

In real world use, this is rarely a problem.  Font family names may
have spaces but typically don't start with numbers or use punctuation
characters.  Yes, I'm sure there are exceptions out there but they
generally aren't used on the web or in interchange situations (e.g.
email).

What *is* still a problem is the way in which browsers recognize as
family names a variety of other font names.  For example, "Arial" is
the name of a font family, names given to individual faces within that
family are *not*.  Incorrect name matching happens with many GDI-based
browsers (Chrome/IE7+8/Opera) which recognize full names (e.g. "Arial
Bold").  It occurs with Webkit browsers on OSX/iOS which recognize
Postscript names (e.g. "Arial-BoldMT").  These browsers will all fail
the CSS 2.1 test suite tests that check for this.  This is a real
problem because authors will use "Arial Bold", see that it works in
their given browser/environment and assume that it will work across
platforms/browsers.

What *is* still a problem is the way in which browsers recognize as
family names a variety of other font names.  For example, "Arial" is
the name of a font family, names given to individual faces within that
family are *not*.  Incorrect name matching happens with many GDI-based
browsers (Chrome/IE7+8) which recognize full names (e.g. "Arial
Bold").  It occurs with Webkit browsers on OSX/iOS which recognize
Postscript names (e.g. "Arial-BoldMT").  The current shipping versions
of Chrome/Safari will all fail the CSS 2.1 test suite tests that check
for this.  This is a real problem because authors will use "Arial
Bold", see that it works in their given browser/environment and assume
that it will work across platforms/browsers.

Regards,

John Daggett

Arial variations illustrating what is and isn't matched:
http://people.mozilla.org/~jdaggett/tests/arialvariations.html

Full name matching:
http://test.csswg.org/suites/css2.1/20110323/html4/font-family-name-013.htm

Postscript name matching:
http://test.csswg.org/suites/css2.1/20110323/html4/font-family-name-014.htm
Received on Saturday, 17 March 2012 03:10:24 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 22 May 2012 03:48:52 GMT