Skip to content

Eta-reduced term has wrongly inferred monomorphic type

Hi,

When creating a file with the following two definitions:

rowtotals xs = map sum xs
rowtotals'   = map sum

And loading this file in GHCi. Asking for the type of the two definitions gives:

*Main> :t rowtotals
rowtotals :: Num b => [[b]] -> [b]
*Main> :t rowtotals'
rowtotals' :: [[Integer]] -> [Integer]

Is this the expected behaviour? I would expect both to have the same polymorphic type.

Cheers, Christiaan

Trac metadata
Trac field Value
Version 7.2.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information