On Tue, Oct 4, 2011 at 12:42 AM, Magicloud Magiclouds
<magicloud.magiclouds@gmail.com> wrote:
Hi,
I have a function:
post :: (ToJson p, FromJson q) => String -> String -> String ->
Map.Map String p -> IO q
Now I'd like to call it like:
r <- post site token "user.addMedia" (Map.fromList [ ("users", users :: ToJson)
, ("medias", medias
:: ToJson) ])
So I got the problem. If I used things like "users :: ToJson", then
class used as a type error occurred. But if I did not use them, since
users and medias were actually different types, then fromList failed,
required the type of medias the same with users.
How to resolve the conflict?
--
竹密岂妨流水过
山高哪阻野云飞
_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe