Polymorphic components, so far

[Ashley Yakeley]

Iavor Diatchki wrote:
>  - option 3: GHC 6.6 style rank-N types.  This one I am less familiar
> with but here is my understanding:
>      * Based on "Boxy types: type inference for higher-rank types and
> impredicativity"
>      * Impredicative (type variables may be bound to schemes)
>      * Sometimes we compare schemes for equality (this is
> demonstrated by the example on ticket 57) and we also use the
> sub-typing by generality on schemes
>      * Again, function types are special

It's buggy in GHC 6.6, see 
<http://hackage.haskell.org/trac/ghc/ticket/1123>.

-- 
Ashley Yakeley