[Haskell] Arrows GUI Library Based on GTK+

[ross at soi.city.ac.uk]

On Sat, Mar 19, 2005 at 07:48:09AM -0700, Kevin Atkinson wrote:
> > Your module uses the arrow interface, but it's actually equivalent to
> > monads.  
> 
> It is?  Than what would "app" look like?

My mistake: FG' is a Kliesli arrow, but FG isn't.

> Has anyone tried to make Fudgets an instance of the Arrow class?

see the stream processors in John Hughes's original paper.

> > - how about: data Event a = NoEvent | Event a
> 
> And what would "a" be?

The thing you currently always pair with an Event, and ignore if it's
NoEvent.

> > - you don't really need mkAFunDef in AbstractFunction, and indeed you
> >   don't need AbstractFunction either -- you could just use Arrow, of
> >   which both (->) and FG are already instances.
> 
> But than can I make a function like "tag" which can either be used as an 
> arrow or a function.

But functions are arrows: (->) is an instance of the Arrow class.