when is defaulting supposed to occur?
Iavor S. Diatchki
diatchki at cse.ogi.edu
Thu Oct 23 16:07:45 EDT 2003
the problem has to do with the monomorphism restriction
see section 4.5.5 (rule 2) (or typing hashell in haskell section 11.5.1
Mark Tullsen wrote:
> Note the following program
> x = 1
> y = x :: Int
> This is accepted by ghc but it is rejected hugs (May 2003 cvs):
> ERROR "IntegerTest.hs":4 - Type error in type annotation
> *** Term : x
> *** Type : Integer
> *** Does not match : Int
> My guess is that hugs is doing defaulting after a "declaration group"
> is type-checked, but that ghci leaves 'x' with type 'Num a', then
> processes further declaration groups, and then does defaulting.
> I don't see that the report specifies this (did I miss it?).
> - Mark
> Haskell mailing list
> Haskell at haskell.org
| Iavor S. Diatchki, Ph.D. student |
| Department of Computer Science and Engineering |
| School of OGI at OHSU |
| http://www.cse.ogi.edu/~diatchki |
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