Macro assertables::assert_err

source · 
macro_rules! assert_err {
    ($a:expr $(,)?) => { ... };
    ($a:expr, $($message:tt)+) => { ... };
}
Expand description

Assert expression is Err(_).

Pseudocode:
a is Err(_)

  • If true, return ().

  • Otherwise, call panic! with a message and the values of the expressions with their debug representations.

§Examples

let a: Result<(), i8> = Err(1);
assert_err!(a);

let a: Result<(), i8> = Ok(());
assert_err!(a);
// assertion failed: `assert_err!(a)`
// https://docs.rs/assertables/8.7.0/assertables/macro.assert_err.html
//  a label: `a`,
//  a debug: `Ok(())`

§Module macros