Macro getopt_rs::opt

macro_rules! opt {
    ($short : literal) => { ... };
    ($short : literal, $long : literal) => { ... };
    ($short : literal, $long : literal, $long_rule : expr) => { ... };
    ($short : literal, $long : literal, $long_rule : expr, $no_short : expr) => { ... };
}

A macro used to generate Opts.

Usage:

• opt!('c' /* Short form and identifier */)
• opt!('c', "ctrl" /* Long form */)
• opt!('c', "ctrl", LongForm::SimpleDash /* Long rule */)
• opt!('c', "ctrl", LongForm::SimpleDash, true /* No short flag */)

If not specified, the fields are set to their defaults.