A Pointless Library Proposal
John Meacham
john at repetae.net
Mon Oct 23 18:23:47 EDT 2006
On Mon, Oct 23, 2006 at 10:43:36PM +0100, Conor McBride wrote:
> This is one thing we've got that we shouldn't flaunt. If I can't have
> Zero, please may I have
>
> >data Naught
>
> >naughty :: Naught -> y
>
> >innocent :: Functor f => f Naught -> f x
>
> or some such?
I am liking the 'Void' idea proposed earlier, so we have
> module Data.Void where
>
> data Void
> deriving(Typeable,Data,Eq,Ord,...) -- ^ a lot of valid classes
> -- are defined for _|_
>
> fromVoid :: forall a . Void -> a
> fromVoid = unsafeCoerce#
as a bonus, with void, we get to be reminded of b-movie titles like
this friday, at your local theater:
"BEWARE! the catamorph from the VOID!"
I am not sure what a catamorph would be, depending on whether it is
preceded by cuddly or deadly I'd say a sidekick on thundercats or a
metamorphic feline killing machine.
speaking of which, there should be a contest among category theorists to
come up with the best definition for a 'Xenomorphism'. I am not sure
what it would be, but I doubt it would be structure preserving..
John
--
John Meacham - ⑆repetae.net⑆john⑈
More information about the Libraries
mailing list