[Haskell-cafe] Re: Kleisli composition operator

[Daniel Fischer]

Am Sonntag, 3. August 2008 16:52 schrieb Roly Perera:
> > I'm obviously missing something basic here but I don't seem to be able to
> > use the >=> operator which is apparently defined in the Prelude and also
> > in Control.Monad.
>
> Sorry, I wasn't very clear in my original posting.  What I meant to say is
> that the compiler seems to be unable to find a definition of >=>.  I get
> the message:
>
> Not in scope: `>=>'
>
> My understanding is that I shouldn't need to import this at all by default,
> and that importing Control.Monad should also pick it up.
>
> > My imports are:
> >
> > import Prelude hiding (abs, lookup, init)
> >
> > import Data.Maybe
> > import Data.List as List hiding (lookup, insert, delete, union, init)
> > import Data.Map as Map hiding (update, delete, union, null, findIndex)
> > import qualified Data.Tree as Tree
> > import Control.Monad
> > import Control.Monad.State
> >
> > Any suggestions anyone?
> >
> > thanks,
> > Roly Perera
>

Which implementation are you using?
IIRC, GHC didn't have it in Control.Monad before the 6.8 branch.