[Haskell-cafe] Name that function =)
Louis J Scoras
louis.j.scoras at gmail.com
Tue Dec 12 13:14:14 EST 2006
On 12/12/06, Brandon S. Allbery KF8NH <allbery at ece.cmu.edu> wrote:
> 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
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?
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