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From: Vladimir Prus (ghost_at_[hidden])
Date: 2005-09-20 01:17:25


On Tuesday 20 September 2005 04:09, David Abrahams wrote:
> Vladimir Prus <ghost_at_[hidden]> writes:
> > I think it would be good to add a target that just runs some command,
> > without creating any files. When such target is built, the command is
> > just run, and no up-to-date checks are made for any files.
>
> Your phraseology is a little confusing, because bjam does all its
> up-to-date checks before deciding to build anything. But anyway, I'll
> ask:
>
> Not even for files that the target may depend on? That seems like a
> needless and restrictive limitation. It seems like it would be more
> useful if the target were only built when its dependencies (if any)
> were outdated.

Originally, "notfile" was indented for running some commands, when there's no
way you can detect if the command should be rerun, or not. Consider this:

notfile test : "qmtest run" ;

Now, I can add as many dependencies as you like, but Boost.Build has no way to
know if that command "qmtest" will produce the same output of the dependencies
are unchanged. So, the command is run unconditionally.

- Volodya

-- 
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build V2: http://boost.org/boost-build2
 

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