[Haskell-cafe] Why does disambiguation in RebindableSyntax sometimes requires type signatures?
lemming at henning-thielemann.de
Mon Nov 2 18:33:03 UTC 2015
On Mon, 2 Nov 2015, Jan Bracker wrote:
> Hi Henning,
> but with type signatures the errors do not occure.
> My best guess for that one is that inferring the correct kinds for lifted data types is not done properly.
I have not followed the previous conversation. A general problem is that
if a top-level function misses a type signature then GHC might choose a
type that is too special, such that it fits one call site but mismatches
another one. It is always a good idea to add type-signatures to top-level
functions. If your problem occurs with local functions and you can solve
it with a type signature then I think this is the way to go.
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