Re: [xsl] enclosing attribute in single quote

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

Dr Sperberg-McQueen,

At 11:45 PM 4/26/2009, you wrote:
> On 21 Apr 2009, at 16:48 , Wendell Piez wrote:
> > I take it the recipient of the data knows that by requiring XML with
> > only single quotes used as attribute value delimiters, they are
> > asking for XML-that-is-not-XML?
>
> Well, that's kind of harsh, isn't it?  XML does allow single quotes to
> be used, so <a x='y'/> is every bit as much a conforming XML document
> as <a x="y"/>.

Yes, I suppose it's a bit harsh, but only a bit. Maybe not 
XML-that-is-not-XML, but hyper-XML.

> If memory serves, ISO 8879 referred to rules of this kind as
> "application conventions".  So they have always been part of the
> story of generic markup.

Indeed, and I recognize the usefulness of application conventions (I 
hope my Balisage paper gets accepted); in fact I advocate them all the time.

But there's also a big difference between such a convention with 
respect to application semantics (where indeed such conventions are 
the grist of the mill) and such a convention that does nothing for 
semantics, but only restricts the tools that can be used.

I also acknowledge that there may be good reasons for such 
conventions (desperate hackers included), which is why I try to be 
nice (I do!). But (as you know) they should be well-controlled and 
carefully scoped, or they will bite you. The very fact that the OP 
had to ask XSL-List how to get a serializer to impose a non-standard 
syntactic restriction is an indication of something.

> Frankly, if the naming and design rules for prominent XML
> vocabularies can require the use of specific namespace prefixes
> for specific namespaces, and expect to elicit conformance instead
> of incredulous laughter, well, then I guess application conventions
> are alive and well and living among us. (I confess that my response
> was incredulous laughter, but that didn't persuade them to change
> the rules.)

Don't get me started on the confusion sown by namespaces into this 
area. (Which isn't meant as a criticism of namespaces, as I don't 
have an alternative to suggest. Just an observation.)

> There may well be SAX serializers which accept an invocation-time
> parameter to prefer single quotes when emitting attribute values
> (I've never looked so I don't know).  If there aren't, it really
> shouldn't be too very hard to write one, to pair it with a SAX
> parser, and to put together a filter that will normalize any
> XML input by emitting it with single quotes only around attributes.

Or, as I said to the OP, write yourself a hyper-XML-syntax serializer 
that does what you want using the XSLT output method="text".

Start with Evan Lenz's XML-to-string converter 
(http://www.xmlportfolio.com/xml-to-string/), which will save you 
some work. Isn't this monstrous? (See, I can be pragmatic too. :-)

Cheers,
Wendell



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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
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