Magic classes for Overloaded Record Fields, overlaps, FunDeps

Simon Peyton Jones simonpj at
Wed Apr 27 11:14:27 UTC 2016

|  > I have been vacillating between type families and fundeps for the ORF
|  > classes. I hadn't fully appreciated this point about overlap, but I
|  > think it is a reason to prefer fundeps, which is the direction in
|  > which I'm leaning. I'd be grateful for feedback on this issue though!

|  The difficulty remains that as soon as you want overlaps in such a way
|  that takes you to FunDeps, it's very difficult to 'mix modes' with type
|  families.

Can one give a standalone explanation of the fundep/type-family/overlap issue here? Or is it explained on a wiki page?


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