On Thu, Sep 27, 2012 at 1:43 PM, David McBride <toad3k@gmail.com> wrote:

I think what he is asking is if try (from lifted) has type

try :: (MonadBaseControl IO m, Exception e) => m a -> m (Either e a)

and simpleHttp is

simpleHttp "googe" :: IO (Result (Response ty))

then how can the whole statement have

try $ simpleHttp "goog" :: GHandler master sub (Either SomeException ByteString)

when the m in both parts of try is the same, it should end up IO not GHandler master sub. So I don't understand why this would work, either.

On Thu, Sep 27, 2012 at 1:33 PM, Brent Yorgey <byorgey@seas.upenn.edu> wrote:

On Thu, Sep 27, 2012 at 10:01:25AM -0700, Bryce Verdier wrote:
> On 9/26/12 6:00 PM, Ertugrul Söylemez wrote:
> >Bryce Verdier <bryceverdier@gmail.com> wrote:
> >
> >> body <- L.try (simpleHttp "http://www.google.com") :: IO (Either
> >>L.SomeException Data.ByteString.Lazy.Internal.ByteString)
> >Almost right, but your type signature is lying. =)
> >
> >
> >Greets,
> >Ertugrul
>
> Thanks for your hint, with a fair amount of head bashing against a
> wall I was able to figure this out. At the end of day I got :
>
> body <- try (simpleHttp "http://www.google.com") :: GHandler
> PlayHaven PlayHaven (Either SomeException ByteString)

Do you need a type signature there at all?

-Brent

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