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Re: [Scheme-reports] the features function
Per Bothner scripsit:
> Kawa has an open-ended set of feature identifiers, in that
> class-exists:CLASSNAME is true if the java class CLASSNAME exists
> in the compile-time environment. This functionality has similar uses
> as the new library clause, and could perhaps be replaced by the latter.
> Still, it is unclear if an implementation with a feature-set pattern
> like class-exists:CLASSNAME is strictly conformant. Perhaps I could
> just say class-exists:CLASSNAME is not a feature-name, but a
> different kind of extension to cond-expand.
I think so. If you provide R7RS cond-expand, you could have features,
library names wrapped in (library ...), and class names wrapped in
(class ...), for example.
> What are the use cases for the features function, except perhaps
> informational, for humans?
The uses of CL *features* seem to be debugging, logging, and similar
orthogonal aspects. It's also possible that the features list could
change at run time due to a change in the program's environment.
With techies, I've generally found John Cowan
If your arguments lose the first round http://www.ccil.org/~cowan
Make it rhyme, make it scan cowan@x
Then you generally can
Make the same stupid point seem profound! --Jonathan Robie
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