Vector of std::function with different signatures

Question

I have a number of callback functions with different signatures. Ideally, I would like to put these in a vector and call the appropriate one depending on certain conditions.

Answer 1

std::function erases the exact type of the function object but preserves the function call signature. If you cannot bind the extra arguments in advance as Jonathan Wakely recommends, you can use a boost::variant< std::function<...>, std::function<...> > as your vector member. At the call site you can then check if the vector contains the right kind of function object and call it accordingly.