25 Mar
2005
25 Mar
'05
8:38 a.m.
Simon Peyton-Jones wrote:
| > | > class Functor f where fmap :: ... | > class Functor m => Monad m where | > ...the usual stuff... | > fmap = liftM | >
It seems overkill to have a whole new language feature to deal with one library issue.
Perhaps it is...
For example, what if Functor T *is* defined explicitly, but in a later module?
I guess it would be the same as what happens now if you accidentally declare the same instance in different modules, i.e., the system would complain about overlapping instances. -- Thomas H