how to include c++ header file in objective c header file

I want to parse xml files in my project recently. I choosed tinyxml. It only have two files. tinyxml2.h and tinyxml2.cpp.

I know a little about objective c++, I can include tinyxml2.h in .mm file. the compiler will treat it as objective c++ source code. But I can not include tinyxml2.h in any .h file.

So, my question is how to include tinyxml2.h in my objective c header file.

thanks in advance.

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