The following code example is taken from the book
C++17 - The Complete Guide
by Nicolai M. Josuttis,
Leanpub, 2017
The code is licensed under a
Creative Commons Attribution 4.0 International License.
// raw code
// "inherit" all function call operators of passed base types:
template<typename... Ts>
struct overload : Ts...
{
using Ts::operator()...;
};
// base types are deduced from passed arguments:
template<typename... Ts>
overload(Ts...) -> overload<Ts...>;