[Swig-user] Apply OUTPUT for CSharp and std::string

[<and...@hi...>]

Hi

I have come across a small problem that surmounts my understanding of typemaps in swig. Please consider the following minimal example:

%include "typemaps.i"
%include "std_string.i"

%{
class TestClass {
 public:
  TestClass();
  virtual ~TestClass();
  bool stringTest(std::string &refString);
};
%}

%apply std::string &OUTPUT { std::string &refString };

class TestClass {
 public:
  TestClass();
  virtual ~TestClass();
  bool stringTest(std::string &refString);
};

While Swig 2.0 parses this without a problem for Python, for CSharp it gives the following error:
TestClass.i(11) : Warning 453: Can't apply (std::string &OUTPUT). No typemaps are defined.

I have tried to find out what is missing by looking at the output of -debug-tmsearch and -debug-tmused, however, I am not enough of a Swig and CSharp expert to make sense of it. Any help is greatly appreciated.

Best regards

Andreas