Macro rgb_fg 

macro_rules! rgb_fg {
    ($red:expr, $green:expr, $blue:expr) => { ... };
}

Constructs an RGB foreground (text) colour code set (to be used in a control sequence)

Examples:

// Get the RGB codes
assert_eq!("38;2;180;15;70", rgb_fg!(180, 15, 70));
// Use in a sequence
assert_eq!("\u{1B}[38;2;180;15;70m", seq!(rgb_fg!(180, 15, 70)));