Bug #605 -- Conditional execution
jwrober at linuxfromscratch.org
Sun Feb 1 19:49:57 PST 2004
Kevin P. Fleming wrote:
> Gerard Beekmans wrote:
>> So, my question to you guys is: what will it take to get this feature
>> implemented? I can justify spending work hours on this, to a certain
>> degree, so I'm perfectly willing to help out implementing it. However,
>> my coding skills aren't up to snuff with what you'd expect to see
>> quality wise, so I'm not sure I could pull it off properly.
> OK, I have begun working on this, I'm about 30% of the way there. I have
> some issues for the group, though:
> - was <if>/<then>/<else> support added in DTD 3.1 or 3.0? I am adding it
> to nALFS and allowing it be used to match the 3.1 DTD (even though James
> as already removed it from the 3.1 syntax document), but I need to know
> if it was in the 3.0 DTD as well.
The v3.1 DTD does not even have <if>, <then>, <else> in it anywhere.
hence the reason I removed them from the syntax doc. Kinda difficult to
document something that does not exist. So, I think the info in the doc
was out of place and those elements do not exist anywhere yet. I am
thinking you are going to need them in v3.2 and up.
> - I'm not keen on the <if> syntax at all... it seems cumbersome and will
> be hard to extend in the future. For DTD 3.2, I'd like to propose the
> <test>"shell test function expression"</test>
> <package-version condition="eq">3.1.2</package-version>
I like this scenario. Looks clean and easy to follow. What would all
of the condition ATTLIST's be? Same as what bash offers now?
> Well, the logic there is bogus, but you see the point: add <and>/<or>
> elements to construct boolean logic (multiple conditions inside <if>
> would be implicitly <and>ed) and provide
> <test>/<package-built>/<package-version> tests. This allows for future
> extensibility, is easier syntax to use and can be used for more complex
> tests than the existing syntax.
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