# Macro std::assert_eq

1.0.0 · source ·

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

Expand description

Asserts that two expressions are equal to each other (using `PartialEq`).

On panic, this macro will print the values of the expressions with their debug representations.

Like `assert!`, this macro has a second form, where a custom panic message can be provided.

## Examples

    let a = 3;
    let b = 1 + 2;
    assert_eq!(a, b);

    assert_eq!(a, b, "we are testing addition with {} and {}", a, b);

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