Macro assert_eq 

macro_rules! assert_eq {
    ($left:expr, $right:expr) => { ... };
    ($left:expr, $right:expr, $($arg:tt)+) => { ... };
}

Asserts that two expressions are equal.

If the assertion fails, a trace message is emitted with the values of both expressions, and then the program panics.

Examples

// This will pass
assert_eq!(1, 1);

// This would fail and emit a trace message
// assert_eq!(1, 2);