[Haskell] Re: manipulating untyped lambda-calculus in Haskell

Chung-chieh Shan ccshan at post.harvard.edu
Sat Apr 30 15:13:38 EDT 2005

Vivian McPhail <vivian.mcphail at paradise.net.nz> wrote in article <001301c54d6c$ba44b980$0301a8c0 at intranet> in gmane.comp.lang.haskell.general:
> It seems that I must be missing something?  Is there a more elegant
> way of doing this?

Check out the "generalized algebraic data types" feature (GADT, one of
its many names), now available in GHC.  One classical example of its use
is to write type-safe interpreters similar to your NL parser.

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a more complicated question. -- George Musser. Color Madness. Oddball maps can
require more than four colors. Sci. Am., January 2003.

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