Joerg,
Aside from the ambiguity Arved has highlighted concerning the use of the
term "code point", I was thinking about the recent decision to hack the
spec so that 'format="1."' becomes acceptable. I already find the
automatic conversion of NCNames to strings distasteful enough. Users
develop bad habits from that sort of under-the-hood convenience, and
that leads to loud complaints about all those fussy quotes when they
become essential.
If I take <character> to be a string literal of length 1, the automatic
conversion of NCNames of length 1 would allow, say,
<fo:character character="A"/>
So when users try
<fo:character hyphenation-character="-"/>
they are understandably upset when the parser barfs.
My inclination is to do away with the automatic conversion and
specifically allow an NCName (with explicit conversion) alongside a
literal when it is considered safe, as it is not in the case of
<character> or format. After all, <string> and <character> don't occur
all that frequently.
See below.
J.Pietschmann wrote:
>
> According to 5.11 "Property Datatypes", the value is a single
> unicode character. I believe the representation is a
> unceremonial single unicode character, or an NCName whose
> string representation has the length 1. I'd parse such
> attributes as an expression resulting in a string, and
> bomb if the string is longer than 1.
> This would accept
> character="'a'"
> character="1 + 1"
> character="from-parent('font-size') - 12"
> which may upset purist, or not.
> An alternative would be to use a custom parser, which accepts
> either a single character (NCName of length 1) or any of the
> functions inherited-property-value(NCName),
> from-parent( NCName), from-nearest-specified-value( NCName)
> and from-table-column( NCName)
> (might even make a bit of sense for hyphenation-char and
> for fo:character's character in very, very strange cases)
A custom parser should not be necessary. The <character> restriction
could be expressed as a constraint on the <string> result, checked at
the property level.
> Just for curiosity: what should happen if the following snippet
> is used:
> <fo:page-sequence master-reference="font-size" font-size="20pt">
> <fo:flow font-size="from-parent(from-parent('master-reference'))"/>
This looks OK.
Peter
--
Peter B. West [EMAIL PROTECTED] http://www.powerup.com.au/~pbwest/
"Lord, to whom shall we go?"
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