std::panic!

macro_rules! panic {
    () => { ... };
    ($msg:expr) => { ... };
    ($fmt:expr, $($arg:tt)+) => { ... };
}

The entry point for panic of Rust threads.

This macro is used to inject panic into a Rust thread, causing the thread to unwind and panic entirely. Each thread's panic can be reaped as the Box<Any> type, and the single-argument form of the panic! macro will be the value which is transmitted.

The multi-argument form of this macro panics with a string and has the format! syntax for building a string.

Examples

fn main() { #![allow(unreachable_code)] panic!(); panic!("this is a terrible mistake!"); panic!(4); // panic with the value of 4 to be collected elsewhere panic!("this is a {} {message}", "fancy", message = "message"); }

panic!();
panic!("this is a terrible mistake!");
panic!(4); // panic with the value of 4 to be collected elsewhere
panic!("this is a {} {message}", "fancy", message = "message");