29 Jul
2013
29 Jul
'13
4:20 a.m.
Incidentally, I think it'd be an improvement to localise the Overlapping/Incoherent flags to particular instance declarations, via pragmas, something like instance C [a] where {-# ALLOW_OVERLAP #-} op x = ....
Similarly {-# ALLOW_INCOHERENT #-}. Having -XOverlappingInstances for the whole module is a bit crude., and might be missed when looking at an instance. How valuable would this be?
+1 It would be nice to have same option for undecidable instances as well.