How to build FParsec for .NET Compact Framework?

Question

I’m writing a small application based on FParsec.

Today, I’m looking for an opportunity to make a version for Compact Framework. Apparently, it is not that simple to build FParsec sources for .NET CF. The FParsecCS library has unsafe code and some references to the types that are not available in CF. Namely, System.Collections.Generic.HashSet, System.Text.DecoderFallbackException, and more.

I’m wondering if there’s any way to make it built. Obviously, I’m trying not to alter the code as it would be hard to update when further versions of FParsec released.

I don’t really care about performance. If there is a generic CharStream that can be used instead of high-performance one you have, that would be quite sufficient.

Thank you for your help.

Answer 1

I don’t have any experience with .NET CF and never tried to make FParsec run on it. However, there’s a Silverlight version of FParsec, which might be a good starting point for a port to .NET CF. The Silverlight version builds on the LOW_TRUST version of FParsec, which doesn’t use any "unsafe" code. Hopefully, the stream size limitation of the LOW_TRUST version won’t be an issue for your application.

The easiest way to deal with the HashSet dependency probably is to implement you own simple HashSet type (based on a Dictionary) that implements the few methods that FParsec actually uses for its error handling. If the DecoderFallbackException is not supported, you can just comment out the respective exception handlers.

If you track your changes with HG, it shouldn’t be difficult to merge in updates to FParsec. Depending on how extensive the changes for .NET CF are, I could also include them in the main source tree for another conditional compiler symbol.