zunino: > ac wrote: > > foo :: [Foo] -> <placeholder 1> > > foo xs = map <placeholder 2> xs > > > > What are the possible type signatures for placeholder 1 and the possible > > expressions for placeholder 2? > > A nice GHCi trick I learned from #haskell: > > > :t let foo xs = map ?placeholder2 xs in foo > > forall a b. (?placeholder2::a -> b) => [a] -> [b] > > Also, the djinn tool might provide some actual expression for placeholder 2. > > Zun.
Yes, it turns out implicit parameters provide a great mechanism for doing type checker queries :) -- Don _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe