Daryoush Mehrtash-2 wrote: > >> singleton :: a -> [a] >> singleton x = [x] >> >> Here F is the identity functor, and G is the list functor. And yes, C=D= >> category of (a subset of) Haskell types. > > Are you saying the function that goes from list functor to singleton > funtor > is a natural transformation? >
Here *singleton* is the natural transformation from the identity functor to the list functor. Daryoush Mehrtash-2 wrote: > > But aren't they functors to different subset of Haskell Types? > They're usually treated as endofunctors on Hask, for reasons Ross Paterson has given. -- View this message in context: http://www.nabble.com/Functor-and-Haskell-tp23166441p23189784.html Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
