Ambiguous type variable

Ketil Z. Malde
23 Jan 2003 15:05:08 +0100

"Simon Peyton-Jones" <> writes:

> R.hs:1:
>     Ambiguous type variable `a' in constraints
>       `Random a' arising from use of `randomRs' at R.hs:4
>       `Num a' arising from the literal `0' at R.hs:4
>     Possible cause: the monomorphism restriction applied to the
> following:
>       f :: Int -> [a] (bound at R.hs:4)

How about explicitly suggesting a type signature?  Referring to
"the monomorphism restriction" will probably not be helpful to
novices, who are the ones who need clear error messages the most.

If I haven't seen further, it is by standing in the footprints of giants