I spent the last 18 months getting the grip of functional programming, starting with learning OCaml and for some weeks now Haskell. Now I want to take the next step and implement some actual application: A simple realtime terrain editor. I've written numerous realtime terrain rendering engines, so this is a familiar topic. And the used recursive algorithms and data structures seem very fit for a functional implementation.

With this being a realtime application I'm naturally looking for the best performance I can get. Now some proponents of OCaml quite frequently complain about Haskell being slow compared to OCaml or F#. But according to the [The Computer Language Benchmarks Game](http://benchmarksgame.alioth.debian.org/) Haskell oftenly beats OCaml, if only by rather small fractions. There remains the problem, that this benchmark takes only very specific samples.

The right thing to do would be to, of course, implement the program in both languages and compare them, but I simply don't want to do double the work.

But maybe other people did comparable applications in OCaml and Haskell and give some statistics?