[Haskell-cafe] Functors and the Visitor Pattern

[Andres Loeh]

> Although, now I'm second guessing myself, because I can't figure out how we
> could create some design pattern that simulates an applicative functor. I'm
> pretty sure the Visitor pattern doesn't take you this far (but I am willing
> to be corrected). So, is there a way to create applicative functors in
> non-functional languages? What would that pattern look like?

Perhaps this paper can answer your question:

Jeremy Gibbons, Bruno C.d.S. Oliveira
The essence of the Iterator pattern
http://web.comlab.ox.ac.uk/oucl/work/jeremy.gibbons/publications/iterator.pdf

HTH,
  Andres

-- 

Andres Loeh, Universiteit Utrecht

mailto:andres at cs.uu.nl     mailto:mail at andres-loeh.de
http://www.andres-loeh.de