Macros

Macros declared in the builtin library.

crash!

macro crash!(...msg)

Ends the process with an optional message: crash!() or crash!("why").

Not a panic: it joins no panic set and no try catches it, so a function that calls it needs no panic specifier and main may use it. The message and a newline go to stderr (nothing when empty), then the process aborts. It expands to crash_with(msg...), so the call never returns and ends its path for the flow checks. What it reports is not final; rely only on "it does not return". A file's own crash! shadows this one.

Example

fn main() -> i32 {
    if false { crash!("unreachable state") }
    return 0
}

See also

crash_with

Generated from Kairo source, Apache-2.0 WITH AdditionRef-Kairo-Runtime-exception.