[Haskell-cafe] Re: [Haskell] View patterns in GHC: Request for feedback

[Jon Harrop]

On Monday 23 July 2007 16:57:08 Simon Marlow wrote:
> Dan Licata wrote:
> > Simon PJ and I are implementing view patterns, a way of pattern matching
> > against abstract datatypes, in GHC.  Our design is described here:
> >
> > http://hackage.haskell.org/trac/ghc/wiki/ViewPatterns
> >
> > If you have any comments or suggestions about this design, we'd love to
> > hear them.  You can respond to this list (and we can take it to
> > haskell-cafe if the thread gets long) or, if you prefer, directly to me.
>
> At the risk of being a spoil-sport, I have a somewhat negative take on view
> patterns...

F# already has active patterns and there are OCaml macros implementing views. 
I have used F#'s active patterns extensively and find them to be extremely 
useful. I can only assume that they will remain similarly useful in Haskell.

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
OCaml for Scientists
http://www.ffconsultancy.com/products/ocaml_for_scientists/?e