2 Checks for [`ToString::to_string`](https://doc.rust-lang.org/std/string/trait.ToString.html#tymethod.to_string)
3 applied to a type that implements [`Display`](https://doc.rust-lang.org/std/fmt/trait.Display.html)
4 in a macro that does formatting.
7 Since the type implements `Display`, the use of `to_string` is
12 println!("error: something failed at {}", Location::caller().to_string());
16 println!("error: something failed at {}", Location::caller());