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

[Francesco Ariis]

On Fri, May 15, 2015 at 09:45:43PM -0500, Peng Yu wrote:
> Hi, I can not find how to check the help page of a function.
> 
> For example, I want to check the help page of "head". How should I do
> it? (":help" doesn't seem to help.)

`:t head` will show the function signature (which in 90% of the cases
is more than enough to understand what the function does).

`:i function` will show the function signature and additionally tell
you in which module it is defined.