[Haskell-cafe] Re: [Haskell] Fixpoint combinator without recursion

[Edsko de Vries]

> Yeah, it's rather cool. IIRC, this style of encoding of recursion  
> operators is attributed to Morris.

Do you have a reference?

> Before the advent of equality coercions, GHC typically had problems  
> generating code for these kinds of definitions. Did you test this  
> with a release version? If so, how did you get around the code- 
> generation problem? Is it the NOINLINE pragma that does the trick?

Yep. Without the NOINLINE pragma, ghc tries to inline the definition of
fac, expanding it ad infinitum (this is a known bug in ghc and mentioned
in the ghc manual). Hugs doesn't have a problem though.

Edsko