Re: [Haskell-beginners] How to check the help page of a function?

GHCi has such a command: :doc <function name>

For example: Prelude> :doc head Prelude head :: [a] -> a

Extract the first element of a list, which must be non-empty.

From package base head :: [a] -> a

Where is it? I don't see it. GHCi, version 7.10.1: http://www.haskell.org/ghc/ :? for help Prelude> :doc head unknown command ':doc' use :? for help. Prelude> -- Regards, Peng