[plt-scheme] a Chez vs. PLT syntax-rules incompatibility

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sun May 16 09:30:09 EDT 2004

At Thu, 13 May 2004 14:22:51 -0400, Benderjg2 at aol.com wrote:
> The above version gives the following error under PLT:
> > syntax: too many ellipses in template in: ...
> [...]
> I verified that the first version does work under Petite Chez Scheme.
> But is the a bug in PLT's syntax rules? Or something that really shouldn't
> work, even in Chez, but just does? (e.g. something that is a bad idea.)

It's a documented extension of Chez (compared to R5RS), where an
identifier must be followed by "at least as many ellipses" in a
template as in the pattern, whereas R5RS requires "as many ellipses".

I had forgotten about this particular extension. My usual strategy is
to implement all extensions found elsewhere (as long as they're
consistent), and I'll look into implementing this one.


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