DData modules

Malcolm Wallace Malcolm.Wallace at cs.york.ac.uk
Thu Jan 13 09:13:08 EST 2005

Ross Paterson <ross at soi.city.ac.uk> writes:

> Also, these modules import Data.Monoid, which contains the non-H98 instance
> Monoid (a -> a), making it (and these) non-portable.

In what sense is
    instance Monoid (a -> a)
not Haskell'98?  It looks perfectly OK to me.  Is it because the two
type variable arguments to (->) are the same?


More information about the Libraries mailing list