fn main() { let _ = format!(concat!("{0}π³πΎππ{"), i); //~^ ERROR: invalid format string: expected `'}'` but string was terminated //~| NOTE: if you intended to print `{`, you can escape it using `{{` //~| NOTE: in this expansion of concat! //~| NOTE: in this expansion of concat! //~| NOTE: expected `'}'` in format string }