Macro define_theme 

macro_rules! define_theme {
    (
        bg: ($bg_r:expr, $bg_g:expr, $bg_b:expr),
        bg_alt: ($bg_alt_r:expr, $bg_alt_g:expr, $bg_alt_b:expr),
        fg: ($fg_r:expr, $fg_g:expr, $fg_b:expr),
        fg_alt: ($fg_alt_r:expr, $fg_alt_g:expr, $fg_alt_b:expr),
        base4: ($base4_r:expr, $base4_g:expr, $base4_b:expr),
        red: ($red_r:expr, $red_g:expr, $red_b:expr),
        orange: ($orange_r:expr, $orange_g:expr, $orange_b:expr),
        yellow: ($yellow_r:expr, $yellow_g:expr, $yellow_b:expr),
        green: ($green_r:expr, $green_g:expr, $green_b:expr),
        cyan: ($cyan_r:expr, $cyan_g:expr, $cyan_b:expr),
        blue: ($blue_r:expr, $blue_g:expr, $blue_b:expr),
        magenta: ($magenta_r:expr, $magenta_g:expr, $magenta_b:expr),
        violet: ($violet_r:expr, $violet_g:expr, $violet_b:expr)
    ) => { ... };
}

Macro to define a theme from a color palette. Generates the pub fn theme() -> Theme function.

Example

define_theme! {
    bg: (0x28, 0x2a, 0x36),
    bg_alt: (0x1E, 0x20, 0x29),
    fg: (0xf8, 0xf8, 0xf2),
    fg_alt: (0x62, 0x72, 0xa4),
    base4: (0x56, 0x57, 0x61),
    red: (0xff, 0x55, 0x55),
    orange: (0xff, 0xb8, 0x6c),
    yellow: (0xf1, 0xfa, 0x8c),
    green: (0x50, 0xfa, 0x7b),
    cyan: (0x8b, 0xe9, 0xfd),
    blue: (0x61, 0xbf, 0xff),
    magenta: (0xff, 0x79, 0xc6),
    violet: (0xbd, 0x93, 0xf9)
}