[Haskell-cafe] Pointfree rank-2 typed function

Bas van Dijk v.dijk.bas at gmail.com
Tue Nov 24 13:44:32 EST 2009

On Tue, Nov 24, 2009 at 6:02 PM, Simon Peyton-Jones
<simonpj at microsoft.com> wrote:
> It used to be, because GHC used to implement so-called "deep skolemisation".  See Section 4.6.2 of
> http://research.microsoft.com/en-us/um/people/simonpj/papers/higher-rank/putting.pdf
> Deep skolemisation was an unfortunate casualty of the push to add impredicative polymoprhism.  However, as I mentioned in an earlier email, I'm currently planning to take impredicative polymorphism *out*, which means that deep skolemisation might come back *in*.

Ok nice because I'm very used to refactor code like: 'f x = g x' to 'f
= g' for all f and g.



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