[plt-scheme] Dybvig's 'case' macro doesn't work?

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Mon Dec 30 10:42:24 EST 2002

At 30 Dec 2002 10:35:07 -0500, Ken Williams wrote:
> > Have you checked whether it works in PetiteChezScheme?
> 
> No, I haven't.  Guess I need to download and install it.

I expect it will work.

> Assuming that Dybvig's macros do actually run correctly on some
> platform, I'm curious about what might have changed between his original
> implementation and PLT Scheme's (apparently) more persnickety
> implementation.

Your example shows one of the more prominent differences: PLT Scheme
attaches lexical information to all parts of an expression, not just
to the atoms.

Other major differences: a phase separation that prevents uses of
certain identifiers in places that Chez will allow, and lexical
information tracks `module' bindings.

There any many smaller differences, too.

Matthew



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