| The C-variadic type `...` has been nested inside another type. | |
| Erroneous code example: | |
| ```compile_fail,E0743 | |
| fn foo2(x: u8, y: &...) {} // error! | |
| ``` | |
| Only foreign functions can use the C-variadic type (`...`). In such functions, | |
| `...` may only occur non-nested. That is, `y: &'a ...` is not allowed. | |
| A C-variadic type is used to give an undefined number of parameters to a given | |
| function (like `printf` in C). The equivalent in Rust would be to use macros | |
| directly (like `println!` for example). |