It's not just the number of things, but the way they combine, as in the rules for argument-dependent lookup (not to be mistaken for unqualified name lookup or t

It's not just the number of things, but the way they combine, as in the rules for argument-dependent lookup (not to be mistaken for unqualified name lookup or template type deduction.) When you have pointers and two or arguably three types of references, and arrays that decay to pointers in some cases, there's a lot of different cases to be considered. It's quite an achievement that it often works the way you want. https://en.cppreference.com/w/cpp/language/adl https://en.cppreference.com/w/cpp/language/adl