Macro date 

macro_rules! date {
    ($year:ident - $month:literal - $day:literal) => { ... };
}

Creates a SAC13 date with a statically known and compile time checked value.

Example

use sac13::prelude::*;

let date = date!(M020 - 04 - 14); // "regular" day
let date = date!(M020 - 13 - 29); // year day
let date = date!(M021 - 06 - 29); // leap day

// the following lines would not compile

// date = date!(M022 - 06 - 29); // M022 is not a leap year
// date = date!(M022 - 04 - 29); // No month except August on leap years and Addenduary have more than 28 days