Simplification of instances
david.waern at gmail.com
Fri Sep 28 19:35:48 CEST 2012
2012/9/28 Simon Peyton-Jones <simonpj at microsoft.com>:
> Ahem. DFuns (what you get from is_dfun of a ClsInst) now have some "silent" arguments, that are added by GHC and are not part of the original instance declaration. See
> Note [Silent superclass arguments] in TcInstDcls.
> But you don't want to print them. Just do what InstEnv.pprInstanceHdr does (in InstEnv) to drop the silent arguments.
> I've added some more comments (commit to come).
I've written a Haddock patch that drops the arguments.
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