Macro year 

macro_rules! year {
    ($year:ident) => { ... };
}

Creates a SAC13 year with a statically and compile time checked value.

Example

use sac13::year;

let year = year!(M020);

let year_zero = year!(A000);
let last_year = year!(Z999);

// The following lines are invalid years (or format) and would fail during compilation:
// let year = year!(m020);
// let year = year!(20020);
// let year = year!(-100);
// let year = year!(20);