Replacing => in place of -> in function type signature

haskell

Solution

This is a bug in GHC 7.6.2. You should try it in the most recent compiler and if it still doesn't give an error there, then you should file a bug report.

Actually, I think this bug is already known and fixed in GHC 7.8.

Problem

I just observed that if instead of `->`, I write `=>` in the type signature definition of a function, it doesn't result in an compile time error. Example code: ``` mysum :: Num a => [a] => a -- Notice => after the list [a] mysum [] = 0 mysum (x:xs) = x + mysum xs ``` Why does this happen ? And is there a way to avoid this ? Compiler Used: GHC 7.6.2 Update: Successful compilation in ideone.

Original source