Re: [xml-dev] RE: XML parsers use what computational power?

On Thu, 2013-04-11 at 02:54 +0200, Bjoern Hoehrmann wrote:
> * Liam R E Quin wrote:
[...]
> >My understanding is that XML is at worst LL(2),
[...]
> The EBNF grammar in the XML 1.0 Recommendation describes a context-free
> language, but [...] Reasons
> for XML being not context free include many of the "WFCs" in the speci-
> fication (not all of them, e.g. numeric character references have to
> refer to a `Char`, and that is a regular problem not encoded in the EBNF
> grammar for reasons of readability among others); one example is that
> `<x a='' a='' />` is not an XML document, and you cannot express that
> attribute names must be unique in a context-free grammar, so XML is not
> LL.

True, thank you for keeping me honest, I was thinking only of the
grammar itself.

Having said that, I still don't think Roger's conclusions clearly and
necessarily follow from his premises... :)

Liam

-- 
Liam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/
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