Traits is imo kind of this, in rust and to a lesser extent c++. At the very least, a templated function can insist on being injected with what it needs to engag

Traits is imo kind of this, in rust and to a lesser extent c++. At the very least, a templated function can insist on being injected with what it needs to engage with the outside world as far as an allocator, IO, error handling, and so on.