12 Feb
2012
12 Feb
'12
6:23 p.m.
On 12/02/2012, at 03:21, Iavor Diatchki wrote:
PS: I wouldn't worry too much about breaking existing code, as long as derived Typeable instances continue to work---I never provide custom ones and, in fact, I think that GHC should no allow them or, at least, give a stern warning when it sees one.
There is no easy way to have derived Typeable instances for data families. Standalone deriving works, but only since 7.2 and only like this: data family T a deriving instance Typeable1 T Presumably, this should be Typeable rather than Typeable1 with the new design. Roman