Macro assert_len_eq_x_as_result 

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

Assert a length is equal to an expression.

Pseudocode:
a.len() = b

• If true, return Result Ok((a.len(), b)).

• Otherwise, return Result Err(message).

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

Module macros

• assert_len_eq_x
• assert_len_eq_x_as_result
• debug_assert_len_eq_x