I just made a pull request to reqwest. I thought this particular one was interesting enough to be worth blogging about, so I am. We know that many C++ family languages have a feature known as function overloading, where two functions or methods can exist with the same name but different argument types. It looks something like this: void use_connector(ConnectorA conn) { // IMPL } void use_connector(ConnectorB conn) { // IMPL } The compiler then chooses which method to call, at compile-time, ba...