On Fri, Aug 13, 2010 at 2:53 AM, Will Kurt <[email protected]> wrote: > So which of these is the canonical implementation of a left fold? Why the > difference in Racket? > For pure aesthetics I like the behavior of Racket in the case of cons, but > for '-' the others seems to make more sense.
I don't think there is a canonical implementation. In Racket is seen as the same function as right fold; it just happens to process the list in a different order and so can be tail recursive. Hence it has the same interface. Racket values consistency and clarity in code. In Haskell left fold is seen as a different function to right fold, and hence has a different interface. Haskell values confusing code so Haskell programmers appreciate having different interfaces for very similar functions (and the type system will catch some errors). HTH, N. PS: Some of the above is not to be taken seriously. _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
