Martijn, Thanks for your comment and advice. Could you explain a little further your thinking? Specifically, what advantage do you find in the applicative notation, and when would you advise using it and when would you advise not using it? Thanks again, I appreciate your help. Darryn. On Fri, 2010-04-02 at 20:26 +0200, Martijn van Steenbergen wrote:
On 3/31/10 12:44, Heinrich Apfelmus wrote:
go Next (Single x t1) = liftM (Single x) (rewrite f t1) go Next (Fork t1 t2 ) = liftM2 Fork (rewrite f t1) (rewrite f t2)
In particular, liftM and liftM2 make it apparent that we're just wrapping the result in a constructor.
A small remark: I prefer using applicative notation for this:
go Next (Single x t1) = Single x <$> rewrite f t1 go Next (Fork t1 t2 ) = Fork <$> rewrite f t1 <*> rewrite f t2
Martijn. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe