At 16:50 17/03/2003 +1100, Bernard James POPE wrote:
You have struck the monomorphism restriction.
See: http://research.microsoft.com/Users/simonpj/haskell98-revised/haskell98-repo...
This is an often tripped over snag in Haskell 98's type system.
Ah, thanks. I'd read that, but didn't understand it's relevance. (I'm still not sure I do: I guess the key gothcha here is the bit about [[ Any monomorphic type variables that remain when type inference for an entire module is complete, are considered ambiguous, and are resolved to particular types using the defaulting rules ... ]] meaning that a definition may need further qualification in different environments?) #g ------------------- Graham Klyne <GK@NineByNine.org> PGP: 0FAA 69FF C083 000B A2E9 A131 01B9 1C7A DBCA CB5E