I don't know how specialised code works in ghc, so I have to ask. Does this actually work? The type of x is never known at the foo' call site, so the specialised version of foo' will only be called if ghc does a run time test on the type when invoking foo'. Does it do that?
-- Lennart
Simon Peyton-Jones wrote:
| class C a where ...
| data MkC = forall a . C a => MkC a
| | foo :: MkC -> ...
| | and I want to specialize foo for when the 'a' in the MkC is, say, Int.
Is
| this possible?
Not directly. But you can say
foo (MkC x) = foo' x
foo' :: forall a. C a => a -> ... foo' x = ... {-# SPECIALISE foo' :: Int -> ... #-}
There's no built-in mechanism I'm afraid.
Simon
_______________________________________________ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
_______________________________________________ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users