[[email protected]: Re: [[email protected]: bug in psyntax?]]

----- Forwarded message from "R. Kent Dybvig" <[email protected]> -----

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From: "R. Kent Dybvig" <[email protected]>
To: [email protected]
Subject: Re: [[email protected]: [SISC-devel] bug in psyntax?]
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This is a known "bug" in Chez Scheme and in the portable syntax-case.
Actually, it's a known bug in R5RS, which the portable syntax-case
doesn't support.

With the R5RS version, you can't do this:

   (define ---)
   (let-syntax (---)
     (define ---)
     (define ---))
   (define ---)

With the syntax-case version, you can, and if you want a local scope,
you can create one like this:

   (let-syntax ((a ---))
     (let ()
       (define ---)
       (define ---)))

I brought this up at the informal implementors workshop several years back
(1998), and there was general agreement that R5RS has it wrong.  If you
want to adhere to the R5RS version, however, it should be sufficient to to
remove the local-syntax-case from chi-top, chi-external, and chi-internal,
and modify chi-local-syntax to call chi-body.

Kent


----- End forwarded message -----

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