[Haskell-cafe] RE: why are implicit types different? (cleanup)

Benjamin Franksen benjamin.franksen at bessy.de
Mon Nov 27 21:02:29 EST 2006

S. Alexander Jacobson wrote:
> Ok, I'm not sure I understand the answer here, but how about a
> workaround.  My current code looks like this:
>     tt = let ?withPassNet=wpn
>              ?withPassNet'=wpn
>              ?withPassNet''=wpn
>          in passNet "passnet" ["user"] regImpl b
> The type of wpn is:
>     wpn :: Ev PassNet ev a -> Ev State ev a
> The individual implicit parameters end up arriving with concrete
> values for a.  If I pass wpn to passNet explicitly, it also appears to
> get converted to a monotype on arrival at the inside of passNet.
> So I guess the real question is, how do I pass a polytype* wpn?

Wrap it inside a newtype, maybe?


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