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Re: Namespaces



On Tue, 16 Aug 2005, Matthias Neubauer wrote:

..., the result still is 2! That's the point! Andre seemed to suggest
at the beginning of this thread that either 1 or "no result" would be
sensible results for this example. I think returning "1" is the wrong
thing here, because this seems to contradict lexical scoping
completely.

I would agree with this if (syntax x) were a variable in the meta-language used in the body of the macro m in:

 (let ((x 1))
   (let-syntax ((m (lambda (form)
                     (let ((x 2))
                       (syntax x)))))
     (m)))

but it is not a variable, since it is quoted in the meta-language, so I don't see a conflict in principle with lexical scoping if the inner x does not bind it.

A possible scoping rule would be that the denotation of a syntax-quoted variable be determined by enclosing bindings in the basement-level language outside the body of the macro itself. This is still lexical scoping, since it still allows one to determine the meaning of the identifier from the lexical context of its use.

Cheers
Andre