[whatwg] Namespaces and tag names in the HTML parser

[Peter Occil]

- "Let the current column be the first col element child of the colgroup 
element" is
not considered ambiguous because the "colgroup element" mentioned is 
understood
to be "the colgroup element in question" (see the beginning of the step: "If 
the current
element is a colgroup, follow these substeps:").  On the other hand, the 
phrase
"While the node is a so-and-so element, etc." (and the patterns mentioned in 
my
earlier message) is ambiguous because it is not known beforehand what kind 
of element
is involved.  (Also, ambiguity issues involving "the first col element 
child" are moot
because, as far as I can tell, an element named "col" in a namespace other 
than HTML
can't be a direct child of an HTML "colgroup" element.)
- The tree construction stage is more generic than other HTML algorithms 
with respect
to namespaces, while most of the rest of the spec deals exclusively with the 
HTML
namespace, making confusion much less likely.

--Peter

-----Original Message----- 
From: Ian Hickson
Sent: Thursday, August 01, 2013 4:41 PM
To: Peter Occil
Cc: WHATWG
Subject: Re: Namespaces and tag names in the HTML parser

On Thu, 1 Aug 2013, Peter Occil wrote:
>
> Sec. 12.2.4 (Tokenization) [...]

I mean not in what is today section 12.

For example, where the spec says "Let the current column be the first col
element child of the colgroup element". Why is that not ambiguous?

Right at the top of the spec it says "Except where otherwise stated, all
elements defined or mentioned in this specification are in the HTML
namespace ("http://www.w3.org/1999/xhtml"), and all attributes defined or
mentioned in this specification have no namespace.". What I'm confused
about is why this is enough for part of the spec, but not other parts of
the spec.

-- 
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