On 12/12/06, Brandon S. Allbery KF8NH
Read the thread more completely; ((->) a) is indeed a monad, but you need to include an additional module to get the definition.
Ahh, okay I did see that. I thought that importing Control.Monad would be sufficient. What I didn't realize is that even though the documentation for Control.Monad says that (->(r)) is an instance, it must not be defined there. Importing Control.Monad.Reader indeed does make it work, thanks for pointing that out again. So I guess my next question would be, looking here http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Monad.html How do I figure out that the instance declaration is actually in the Reader module? Is it just because the (->) constructor is special -- or just not hyperlinked? -- Lou.