Prelude> let mapabs = map abs
I just fired up ghci:
λ> let mapabs = map abs
λ> :t mapabs
mapabs :: Num b => [b] -> [b]
ghc 7.10.1
> The monomorphism restriction is turned off by default in ghci since
> version 7.8.1, so you'll see this behavior with newer versions of GHC
> and the original behavior with older ones.
I'm using an old version (7.6.3) on Debian. I'll try to install a newer
version.
Thank you for all these answers.