新工具集：原始F＃模块或从OCaml移植

Question

New language is interesting only if I can use new libraries. So I want to know what new libraries I can use in .net with F#. If F# is compatable with ML/OCaml what Ocaml libraries are ported to F# or can be ported. I'm interesting in signal processing/voice recognition, logic programming/SLD resolution libraries in .NET.

Answer 1

I don't think there is a large number of ML/OCaml libraries that have been ported to F#. The F# programming style has become quite different to what people use in ML/OCaml, so an ML/OCaml library would feel a bit foreign to F# programmers.

There are however some projects that cross-compile in F# and OCaml. F# compiler itself used to be like that and I believe that Slayer from MSR is (or was?) another example. However, for the two domains you mentioned, I'm not aware of any F# library around.

If you're interested in compiling OCaml code in F#, then here are a few things that may help you:

• The larger language limitation when porting OCaml code to F# is that F# doesn't support functors.
• Some standard OCaml libraries are implemented in the FSharp.PowerPack.Compatibility.dll assembly (which can be found in F# PowerPack )

Answer 2

F# includes some ports from OCaml such as the Set and Map collections. Other concrete data structures can be easily ported, such as the purely functional data structures from Chris Okasaki's excellent monograph . I described a heap sort based upon his leftist heap here in OCaml and F#. I published a more thorough review of several purely functional heaps in F# here . However, F# does not seem to be capable of expressing abstract data structures (eg catenable lists abstracted over queues) very well because it lacks the higher-order module system that Okasaki uses so expertly. I have also posted some other translations like this Burrows-Wheeler transform in OCaml and F#. OCaml has a lot of awesome libraries like ocamlgraph but they are often hard or impossible to translate directly because F# lacks core language features like higher-order modules, polymorphic variants, macros and so on.

Microsoft were the first F# adopter, of course, moving their TrueSkill ranking system (used in Halo 3 and Bing AdCenter) and their third-party driver verifier software from OCaml to F#.

The Coherent PDF command-line tools for manipulating PDF documents are one of the few code bases being cross compiled in both OCaml and F#.

We translated our Smoke Vector Graphics engine and our (discontinued) Presenta application from OCaml to F# and it is now sold as F# for Visualization . The translation was certainly made easier by the similarity between the languages but it still took days to do and there is no way we'll be cross compiling.

Most of the code being translated from OCaml to F# is commercial because F# is primarily a commercial language and, consequently, commercial users of OCaml are migrating to F#. Open source F# may begin to take off following the recent release of F# itself as OSS but it is early days yet.

As for your specific topics (eg signal processing), I'm not sure what to recommend beyond binding to FFTW, which I described in Visual F# 2010 for Technical Computing .

Answer 3

I've found one library that supports evolutionary algorithms development.

F# Artificial Intelligence Library - An Implementation of Differential Evolution: http://fsai.codeplex.com/documentation?version=11

about evolutionary algorithms there: http://en.wikipedia.org/wiki/Evolutionary_algorithm

Also there is a short discussion about "nice to have" SLD resolution engine on F# (and one link to prolog ported to C#) http://cs.hubfs.net/forums/thread/6676.aspx

That's all...