[asdf-devel] component-class for files selected on basis of *features*

[Faré]

On Wed, Dec 7, 2011 at 14:55, Nikodemus Siivola
<nikodemus at random-state.net> wrote:
> I want to define a component class PORT-FILE, to be used like this:
>
> :components ((port-file "ccl" :when :ccl)
>             (port-file "clisp" :when :clisp)
>             (port-file "sbcl-x86" :when (and :sbcl :x86))
>             ...)
>
> The implementation I have adds AROUND methods for
>
>  PERFORM (LOAD-OP PORT-FILE)
>  PERFORM (LOAD-SOURCE-OP PORT-FILE)
>  PERFORM (COMPILE-OP SOURCE-FILE)
>
> and does CALL-NEXT-METHOD only if the feature test passes -- which
> seems to work well enough, but is there a better place to hook into?
>
That works indeed. I don't have any better option to offer,
except maybe to make your featurization a mixin.
Also if you rely on 2.018 or later, you can use asdf::featurep internally.
You then need :and rather than cl:and, though.

I wish I could say "just use XCVB" at this point, but
XCVB isn't as portable or readily available as ASDF.

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