Re: Overloaded function and implicit parameter passing

23 Oct 2000


      On 23-Oct-2000, José Romildo Malaquias <romildo@urano.iceb.ufop.br> wrote:
...
------------------------- cut here
module Main where
class C a where
    f :: (?env :: Integer) => a -> Integer
instance C Integer where
    f x = ?env + x
main = putStrLn (show (f (45::Integer) with ?env = 100))
------------------------- cut here
...
$ ghc -fglasgow-exts Test1.hs -o test1
Test1.hs:7:
    Unbound implicit parameter `env_rJX :: Integer'
    arising from use of `env_rJX' at Test1.hs:7
...
Would anybody comment on what is going on with GHC?
That sure looks to me like a bug in GHC's support for implicit
parameter passing.

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