11 Dec
2007
11 Dec
'07
10:19 a.m.
On Dec 11, 2007 9:20 AM, Duncan Coutts
So my suggestion is that we let classes declare default implementations of methods from super-classes.
Does this proposal have any unintended consequences? I'm not sure.
Please discuss :-) It creates ambiguity if two classes declare defaults for a common
superclass.
My standard example involves Functor, Monad, and Comonad. Both Monad and
Comonad could provide a default implementation for fmap. But let's say I
have a type which is both a Monad and a Comonad: which default
implementation gets used?
I'm disappointed to see this objection isn't listed on the wiki.
--
Dave Menendez