paterson's arrow notation in scala?

Meredith Gregory wrote:
> Is there an implementation of Paterson's arrow notation for Scala?

http://scala.sygneca.com/code/arrows

Eric, et al,

Cheers!

Best wishes,

--greg

On Thu, Jan 8, 2009 at 2:53 PM, Eric Willigers <ewilligers@gmail.com> wrote:

Meredith Gregory wrote:

Is there an implementation of Paterson's arrow notation for Scala?

http://scala.sygneca.com/code/arrows

--
L.G. Meredith
Managing Partner
Biosimilarity LLC
806 55th St NE
Seattle, WA 98105

+1 206.650.3740

http://biosimilarity.blogspot.com

[ note that my name is somewhere on that page ;-) ]

I think it is possible to add such a notation to the language.
(see http://lucdup.blogspot.com/2008/11/scala-monads-and-arrows.html
 for the most important method to define syntax for)

Whether or not it is desirable is another thing: one of
the main goals of Scala is to be scalable at the library
level rather than at the language level.

On the other hand:
I am not sure if elegant arrow notation
(closely resembling the one of Haskell) can be defined as an internal DSL.

(2)

I saw:

trait Arrow[I,O] extends Function1[I,O]

I have this feeling that arrows that extend Function1 are monads
(applicative arrows are monads)

is there not a way to postpone this extends to implementations
that really are applicative?

For example:

class PureArrow[I,O](f: I => O) extends AbstractArrow[I,O] with Function1[I,O]

just a suggestion

Luc


On Fri, Jan 9, 2009 at 12:26 AM, Meredith Gregory <lgreg.meredith@gmail.com> wrote:

Eric, et al,

Cheers!

Best wishes,

--greg

On Thu, Jan 8, 2009 at 2:53 PM, Eric Willigers <ewilligers@gmail.com> wrote:

Meredith Gregory wrote:

Is there an implementation of Paterson's arrow notation for Scala?

http://scala.sygneca.com/code/arrows

--
L.G. Meredith
Managing Partner
Biosimilarity LLC
806 55th St NE
Seattle, WA 98105

+1 206.650.3740

http://biosimilarity.blogspot.com

--
  __~O
 -\ <,
(*)/ (*)

reality goes far beyond imagination