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Re: code and blockcode

From: Laurens Holst <lholst@students.cs.uu.nl>
Date: Wed, 13 Jul 2005 02:57:52 +0200
Message-ID: <42D46710.1020704@students.cs.uu.nl>
To: Simon Siemens <Simon.Siemens@web.de>
Cc: XHTML-Liste <www-html@w3.org>

Simon Siemens wrote:

> Yes, we have additional semantics by "code" and "blockcode". But what 
> is the usage? It's the same as adding a tag for exclamation sentences 
> like:

Well, as a use case, look at the following example [1]:

<blockcode class="program">
<l>program p(input, output);</l>
<l>begin</l>
<l>   writeln("Hello world");</l>
<l>end.</l>
</blockcode>

With the following CSS (slightly modified):

blockcode { counter-reset: linenumber }

blockcode l:before {
    position: relative;
    left: -1em;
    counter-increment: linenumber;
    content: counter(linenumber);
}

This would create automatic line numbering, which makes sense for code, 
but not for other preformatted content such as a poem where whitespace 
matters [2].

Also, the blockcode example [3] shows how class is used to designate the 
language of the code. Given the objections that I mentioned with regard 
to naming conventions (assembly or asm?), misuse (js for c++), and the 
limited usefulness of such information, I think that this is probably 
the best solution. Downside: outside the context of the webpage and its 
styling, e.g. in search engines, it will not be possible to reliably 
detect the language.

Although a clever search engine will immediately recognise blockcode 
with class="Perl" as Perl code, of course. I’d say based on a mapping of 
common classnames for languages (e.g. "asm" -> "assembly", "z80" -> 
"assembly", "py" -> "python") and perhaps some partial matching and 
probability calculations, the language contained in a block of code can 
be determined relatively reliable. Especially when combined with 
analysis of the content of the blockcode. It is not simple, but a ‘code 
search engine’ would be a specialised piece of software anyway. And if 
standardising of some class values is necessary, a microformat could 
take care of that... (if I correctly grasped the concept of microformats :))


~Grauw

[1] http://www.w3.org/TR/xhtml2/mod-text.html#sec_9.7.
[2] http://www.w3.org/TR/xhtml2/mod-structural.html#sec_8.7.
[3] http://www.w3.org/TR/xhtml2/mod-structural.html#sec_8.2.

-- 
Ushiko-san! Kimi wa doushite, Ushiko-san!!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Laurens Holst, student, university of Utrecht, the Netherlands.
Website: www.grauw.nl. Backbase employee; www.backbase.com.
Received on Wednesday, 13 July 2005 00:57:54 GMT

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