Re: [Boost-build] How to stop propagating properties to dependents.

Subject: Re: [Boost-build] How to stop propagating properties to dependents.
From: Alexey Pakhunov (alexeypa_at_[hidden])
Date: 2009-03-30 14:23:14

(Hit a wrong button. Resending to the mailing list.)

> The primary question is how those relevant properties can be determined.
For standard
> generators such as compilers it would be reasonable to look at all 'flags'
> settings for the corresponding rules and see which properties are in use
there.

Are there any non-standard generators that do not use 'flags'? If there are
it still should be possible to convert all standard generators but keep
compatibility no filtering mode for others. I think the main problem would
be the bugs in existing build scripts exposed by changes in the behavior of
the standard generators.

> Also, there should be a mechanism to mark a specific feature as relevant
or
> irrelevant for specific generator, or for specific metatarget (*).

There is a way to call a rule via "<conditional>@my-rule". We can define
similar "<filter>@my-rule" feature to do the job. BTW can we use
"<conditional>" to remove properties inherited from a parent?

I think starting with "<filter>" syntax is a better idea. It is not as
intrusive as changing all generators. Once the concept proves itself we will
be able to apply more radical changes to the generators.

-- 
Best regards,
 Alexey Pakhunov.