Lambda over types.

Keith Wansbrough
Fri, 22 Mar 2002 09:34:08 +0000

anatoli <> writes:

> ghc -fglasgow-exts -fallow-undecidable-instances allows =

> constructs which amount to lambda abstraction over types. =

> I've written a small untyped lambda calculus interpreter =

> in the Haskell class/instance sublanguage, just to prove
> this point. (The terms are Haskell *types*.)


Some time ago I wrote a Turing machine evaluator in Haskell types with un=
decidable instances.  It's described at



--KW 8-)
-- =

Keith Wansbrough <>
University of Cambridge Computer Laboratory.