Basically what the title says, but here is an example:
CppHeaderParser will fail to parse code like below:

namespace i {
	struct Human {
		int t1;
	};
}
namespace w {
	struct Human {
		int t2;
	};
}

The issue is caused by the following code:

if not key.endswith("::") and not key.endswith(" ") and len(key) != 0:
 if key in self.classes:
 race_print("ERROR name collision:", key)
 self.classes[key].show()
 newClass.show()
 assert key not in self.classes # namespace collision

inside _CppHeader::_evaluate_class_stack
Sadly im not sure if there is any easy way to fix this problem since it is actually caused by the fact that CppHeaderParser doesn't include normal namespaces in the name of a class.
A possible fix would be to include the namespace in the name as well which would force everyone to rewrite their code.
Another possible fix would be to distinguish between classes with a unique hash which also includes the namespace.
Edit: Add example and fix code indention