[Pre-pre-RFC] "splatting" for named arguments and function overloading

Nadrieril:

C++ FFI is my main motivation for having any kind of overloading. I don't particularly want overloading in the language outside of that, it just so happened that there was a tiny-looking syntactic feature that would give it "for free".

Wouldn't an #[attribute] do better here than trying to give extra meaning to other Rust code especially on the "[not wanting] overloading in the language outside of that" front? (Assuming C++-calling-Rust FFI direction.)