[Haskell-cafe] Type checking of partial programs
zunino at di.unipi.it
Thu Mar 20 16:36:43 EDT 2008
> 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.
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