By my little experience with GHC 7.* it seems that this version is
more deterministic when deriving instances. For example
if there is a general instance declaration such is:
instance C1 x= C2 x where
then the absence of the C1 instance becomes an error. C1 instance
becomes a
Well, this is not so general. It seems to be associated to
the inferred contexts in automatically derived instances (generated with the
deriving keyword). I will write a clear example as soon as I make sure
what is different between GHC 6 and 7 about this.
2011/4/18 Alberto G. Corona
