The only GCC error that apologizes (that I know of): https://godbolt.org/z/GMxz5c339 https://godbolt.org/z/GMxz5c339 "sorry, unimplemented". It really felt ou

The only GCC error that apologizes (that I know of): https://godbolt.org/z/GMxz5c339 https://godbolt.org/z/GMxz5c339 "sorry, unimplemented". It really felt out-of-place when I first encountered it, but I think it messages intent a bit more than a simple "unimplemented" error message. It at least suggests that this is a shortcoming of the current implementation, so it might get implemented in a later version. Having said that clang also doesn't implement this, and the error message doesn't apologize: "error: cannot compile this lambda conversion to variadic function yet"