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c++iosxcodenamespacesobjective-c++

Unknown type name 'using' in XCode

I have a project (MyLib) inside my main project (MainApp). When I build the MainApp, XCode gives me an error in one of the .h file of MyLib:

using namespace cv;

The error message is:

Unknown type name 'using'

If I build MyLib alone, I do not have any error.

Solution

  • I expect that header file is included from a .m (Objective-C) file?

    Change the extension to .mm (Objective-C++) and it should work fine.