Re: [Haskell-beginners] confused by <-

On 9/27/12 10:33 AM, Brent Yorgey 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 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 That is an awesome question. Originally I tried:

body <- try (simpleHttp "http://www.google.com") and I got this error: playhaven.hs:54:73: Ambiguous type variable `a0' in the constraints: (Show a0) arising from a use of `show' at playhaven.hs:54:73-76 (Exception a0) arising from a use of `try' at playhaven.hs:52:13-15 Probable fix: add a type signature that fixes these type variable(s) So I figured that adding the type signature would help with it. If you know of another way to make this work I would really like to hear about it. Thanks, Bryce

_______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners