Objective-C++ and .cpp files in Xcode

Question

I'm trying to make a simple Objective-C++ applicaiton. All of my code is compiling fine, including the use of C++ in Objective-C classes, until I try and add a C++ class to the mix. I've created a simple C++ class:

Test.h

class Test {

};

and included this file in a Objective-C class (with a .mm extension) and I get the following build error:

error: expected '=', ',', ';', 'asm' or '__attribute__' before 'Test'

Clearly I'm missing some simple concept here. I'd appreciate some enlightment.

Answer 1

Well, after scanning more closely over Apple's Documentation, it looks like the answer to to use the __cplusplus preprocessor flag in the header file. Here's what the code looks like now:

#ifdef __cplusplus

class Test {

};

#endif

Answer 2

Shouldn't the preprocessor command required be:

#ifdef __cplusplus

Answer 3

helixed's answer will not help, your class will be just skiped by preprocessor if __cplusplus undefined.

Most of all you trying to include C++ class from *.m file, try to rename it to *.mm. This solve the same problem on my side.

Answer 4

In Xcode 6 there is the following option:

Apple LLVM 6.0 - Language -> Compile Sources As

You can set that to Objective-C++ and then the file extension does not matter. This is particularly useful if you are working cross-platform and need to use other file extensions.