[Haskell-cafe] ScopedTypeVariables in let-bindings (not where-bindings!) and bug 4347

[Paolo Giarrusso]

On Sat, May 21, 2011 at 16:27, Brandon Allbery <allbery.b at gmail.com> wrote:
> On Sat, May 21, 2011 at 10:17, Paolo G. Giarrusso <p.giarrusso at gmail.com>
> wrote:
>>
>> First, thanks to you and everybody for the alternative. But I'm still
>> convinced that the syntax is supposed to work, and you're just
>> workarounding the bug.
>
> Hm, I think we have differing expectations; the syntax everyone presented is
> the one that is normally used for such things in ghci, and while perhaps the
> one you tried is supposed to work, it's a bit unusual and therefore probably
> not very well tested.

Yes, it was my guess as well - and for some reason I missed the usual syntax.
A sincere question about the usual syntax: where do you learn it? It's
needed seldom enough that I don't see it often in tutorials. And
Googling for "let type signature haskell" leads me to the Haskell
report or to ScopedTypeVariables.

Cheers,
-- 
Paolo Giarrusso - Ph.D. Student
http://www.informatik.uni-marburg.de/~pgiarrusso/