Macro at_least_one 

macro_rules! at_least_one {
    ($element:expr; 0) => { ... };
    ($element:expr; $count:expr) => { ... };
    ($($element:expr),+ $(,)?) => { ... };
}

Create an initialized AtLeastOne instance.

This macro is similar to the vec! macro, but doesn’t support creating an empty AtLeastOne instance.

Security

This macro must only be used in tests, because it skips the TrustedPreallocate memory denial of service checks.