The following code is accepted by hugs and hbc, but produces an error in ghc-4.04-1
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module Bug where
infix 5 |-
infix 9 :=
data Equal = Char := Int
(|-) :: Int -> Equal -> Bool
0 |- x:=y = 1 |- x:=y
2 |- (x:=y) = 0 |- x:=y
_ |- _ = False
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Bug.hs:8:
`|-' is not a data constructor
In the pattern: 0 |- x := y
Compilation had errors
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As one can guess, 0 |- x:=y is parsed
correctly as 0 |- (x:=y) when on left hand side,
but not on the right hand side.
