Mangle a name to use as a function in c++

I want to mangle a name passed to a macro to use it as a name of a function. For example I have a macro called foo as below:

#define foo(name) void name(cost string& in) { \\do something}

But this macro can call with parameter like this foo(Bar::do) so I have to change the name to proper one to use it as a function.

Is there any way to able to implement this? I use c++11 and g++5.x.