Hello everyone, I am developing a toolset in which I have several (multiparameter) type classes; It is often the case that I can only define a data-type X as an instance of one such class (say A), if X is an instance of another class (say B); The thing is that, while it is hard for me, because of all the type parameters that I have to deal with, to add 'X is an instance of B' to the context cxt_A in 'instance cxt_A => A X' ghc is always able to correctly infer all type parameters; In fact, I always get: 'Could not deduce (B X t1 ... tn) from the context cxt_A arising from ... Probable fix: add (B X t1 ... tn) to the context cxt_A ...' In my case, this is the fix that I always need: most of the times, I am just copy-pasting (B X t1 ... tn) to cxt_A! Is there a way, say a compilation option, to avoid this? can anyone please help me here? :) thank you very much -- João Paulo Fernandes Universidade do Minho www.di.uminho.pt/~jpaulo