Macro assert_err_as_result

macro_rules! assert_err_as_result {
    ($a:expr $(,)?) => { ... };
}

Assert expression is Err.

Pseudocode:
a is Err(a1)

• If true, return Result Ok(a1).

• Otherwise, return Result Err(message).

This macro provides the same statements as assert_err, except this macro returns a Result, rather than doing a panic.

This macro is useful for runtime checks, such as checking parameters, or sanitizing inputs, or handling different results in different ways.

Module macros

• assert_err
• assert_err_as_result
• debug_assert_err