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Status
As of April July 2007, the C# code generator and runtime are compatible in sync with development of ANTLR v3. 0b8. As before, development progress going forwards is likely to be sporadic.
The code generation templates and the runtime library itself are essentially feature complete with respect to the reference Java version in v3.0b8. The C# (and Python) targets have a definite advantage due to the existence of native StringTemplate implementations. Unfortunately, automated tests are yet to be written for the target. Some basic sanity check are done however - primarily checking that the sample grammars in the examples-v3 archive works as designed.
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As with all other targets, the C# code generation and runtime are modelled on the Java version. This means the C# target supports features such as grammar development/prototyping and remote debugging with the AntlrWorks GUI which is very important for ANTLR users. Developing radically different code output is left as an exercise to the reader 
Target Platforms
Microsoft .NET v1.1 and v2.0
Mono
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