syntactic sugar for "arrows"

[Ross Paterson]

John Hughes has defined a new abstract view of computation, in his
(currently draft) paper "Generalising Monads to Arrows", at

        http://www.cs.chalmers.se/~rjmh/Papers/arrows.ps

Time to ditch all those dusty old monads and upgrade to arrows.
However the point-free style of that paper won't appeal to everyone.
I've placed a proposal for a Haskell extension with a do-notation-style
syntax for arrows at

        http://www.soi.city.ac.uk/~ross/notes/ArrowsInHaskell.html

Comments welcome.

-- Ross Paterson