On Fri, Jul 5, 2013 at 11:03 PM, Ömer Sinan Ağacan omeraga...@gmail.comwrote:
There's an implicit quantifier in type of `f`, like this: `f :: forall
a. a - ListF a a`. When I add `ScopedTypeVariables` and `forall a.
...` in top level definition, it's like all `a`s in scope of top level
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On 08/07/13 19:50, Chaddaï Fouché wrote:
On Fri, Jul 5, 2013 at 11:03 PM, Ömer Sinan A?acan
omeraga...@gmail.comwrote:
There's an implicit quantifier in type of `f`, like this: `f ::
forall a. a - ListF a a`. When I add `ScopedTypeVariables` and
Hi all,
I came across an interesting type checker error, a function is
accepted in top level, but rejected by type checker when moved to
`where ...` clause.
I moved required code to a new module for demonstration purposes:
module Bug where
fix :: (a - a) - a
fix f = let x = f x in
If you remove the type signature from f in the where clause it will
work. The reason is because the type signature listed there, the a is
a different a than in the top level signature. If you change it from
a to x, it says it should be the a that you can't seem to specify.
If you add the pragma
If you add the pragma ScopedTypeVariables to your file, it works the
way you would assume. However you will have to change the toplevel
signature to iterateListF :: forall a. (a - a) - a - Fix (ListF a)
in order to make it work (added the forall a.).
Thanks, that worked.
As far as I
