Re: [Haskell-cafe] Re: How Albus Dumbledore would sell Haskell

On 21/04/07, apfelmus wrote:

Dan Weston wrote:

...

-- Why is this not in Prelude? dup x = (x,x)

It is (almost). It's called

join (,)

It's unfortunate that the Monad instance for ((->) e) isn't in the Prelude.