Re: cvs commit: fptools/libraries/base/Data IntMap.hs Map.hs Sequence.hs Set.hs fptools/libraries/base/Data/Generics Instances.hs Twins.hs

8 Jan 2006


      Simon Peyton Jones wrote:
...
simonpj     2006/01/06 07:51:23 PST
Modified files:
    libraries/base/Data  IntMap.hs Map.hs Sequence.hs Set.hs 
    libraries/base/Data/Generics Instances.hs Twins.hs 
  Log:
  Eta-expand some higher-rank functions.  GHC is about to
  move to *invariant* rather than *contra-variant* in function
  arguments, so far as type subsumption is concerned. These
  eta-expansions are simple, and allow type inference to
  go through with invariance.
Why drop contra-variace?

Jim

Jim Apple

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