macro_rules! assert_const { ($len:expr) => { assert!($len > 0); debug_assert!($len < 0); }; } fn main() { assert!(true); assert!(false); assert!(true, "true message"); assert!(false, "false message"); let msg = "panic message"; assert!(false, msg.to_uppercase()); const B: bool = true; assert!(B); const C: bool = false; assert!(C); assert!(C, "C message"); debug_assert!(true); // Don't lint this, since there is no better way for expressing "Only panic in debug mode". debug_assert!(false); // #3948 assert_const!(3); assert_const!(-1); }