Hi again, I noted Gour filed a ticket for 'allowing arbitrary expressions as marshallers'.
This sounds interesting, but I wonder which would be the most sensible implementation strategy. Do you suggest to implement hs98 expressions using the existing framework ? Is there some existing code that could be reused ? Apart from that, I think the following additional default marshallers would make sense: a) If the hs type is defined in an {# enum ... #} hook and the C type is integral, use (fromEnum/toEnum . cIntConv) as default. b) If the hs type and C type match, and are of the form (Ptr a), use 'id' as default. This is really useful when working with opaque pointers, but maybe there are type-safety related reasons why this shouldn't be done. c) Additionally, we could allow the user to add other default marshallers, depending on the combination of hs/C type. If I recall correctly, Duncan had some ideas for this one ? best regards, benedikt