Adding an ignore function to Control.Monad

[Henning Thielemann]

On Mon, 14 Dec 2009, Gwern Branwen wrote:

> You'll remember the last one wound up being:
>
> # Nothing
> - David Menendez
> - Henning Thielemann (?)
> - John Meachem (?)

What does it mean to be in category Nothing? I like the 'ignore' function, 
the name is not important for me and I prefer the Functor constraint.


> # Just
> ## Control.Monad.ignore :: m a -> m ()
> - Isaac Dupree
> - Martijn van Steenbergen
> - Maurí­cio
> - Michael Snoyman
> - Neil Mitchell
>
> ### Control.Monad.ignore::  f a -> f ()
> - Edward Kmett
>
> ## Control.Monad.void m a -> m ()
> (or void :: f a -> f ())
>
> - Don Stewart
> - Iavor Diatchki
> - Jeff Wheeler
> - Johann Tibell
> - Malcolm Wallace
> - Michael Snoyman (as well)
> - Nicolas Pouillard
> - Stephan Friedrichs
>
> ## Control.Monad.discard :: f a -> f ()
> - Nicolas Pouillard
> - Wolfgang Jeltsch