[Haskell-cafe] Pointfree composition for higher arity

[Mike Dillon]

begin Stephen Tetley quotation:
> On 17 February 2010 16:05, Mike Dillon <mike at embody.org> wrote:
> ...
> 
> > Are you kidding me? I love writing code like this:
> >
> >    ooooo = bunting bunting cardinal thrush blackbird
> >
> > :)
> 
> Hi Mike
> 
> Thanks! - it took me a surprising amount of time to get from this
> (where I cheated and used an online 'combinator calculator'):
> 
> psi :: (b -> b -> c) -> (a -> b) -> a -> a -> c
> psi = c (b s (b (b c) (b (b (b b)) (c (b b (b b i)) (c (b b i) i)))))
> (c (b b i) i)
>   where
>     c = cardinal
>     b = bluebird
>     s = starling
>     i = idiot
> 
> ... to this:
> 
> psi :: (b -> b -> c) -> (a -> b) -> a -> a -> c
> psi = cardinal (bluebird starling (bluebird cardinalstar dovekie)) applicator

I just typed a bunch of bird names together, saw that the signature
appeared to be "ooooo", and ran a quick test to confirm :)

-md