redox::assert!

( $ cond : expr ) => (
if ! $ cond {
panic ! ( concat ! ( "assertion failed: " , stringify ! ( $ cond ) ) ) } ) ; (
$ cond : expr , $ ( $ arg : tt ) + ) => (
if ! $ cond { panic ! ( $ ( $ arg ) + ) } ) ;

Ensure that a boolean expression is true at runtime.

This will invoke the panic! macro if the provided expression cannot be evaluated to true at runtime.

Examples

// the panic message for these assertions is the stringified value of the
// expression given.
assert!(true);

fn some_computation() -> bool { true } // a very simple function

assert!(some_computation());

// assert with a custom message
let x = true;
assert!(x, "x wasn't true!");

let a = 3; let b = 27;
assert!(a + b == 30, "a = {}, b = {}", a, b);