[plt-scheme] Yet another cute idea

From: Noel Welsh (noelwelsh at yahoo.com)
Date: Mon Sep 30 11:19:51 EDT 2002

Ok, my turn to ramble.

One of the nice things about match is that it allows
pattern matching to use simple visual representations.
 Because of its constrained applicability it isn't
necessary to disambiguate lists from general sexps. 
I'm not sure if your proposals will be as easy to use.
 If it requires extra syntax then it may lose one of
the main benefits (to me) of match.

Haskell has gone further than ML in its pattern
matching but there are still limits (perhaps a
Haskeller can comment here).  It might be interesting
to check out the state of Haskell.  Here's one link:


The work on predicate dispatch, which subsumes ML
pattern matching, multimethods, and everything else,
might be interesting.  However it doesn't really
address your original desire to bind variables using
pattern matching.

> 6. Finally, I want a simple way to extend the set of
> patterns, so you
>    could just (import foo) and get more pattern
> keywords. 

Now this is a tough one.  The modularity issues of
composing languages are still an open research issue
AFAIK.  Shriram's work on macros and micros should
provide some inspiration.  I imagine the monadic
interpreter guys also have something to say.  The Maya
approach (multiple dispatch over syntax) may also be



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