Macro option_set::option_set

macro_rules! option_set {
    ($(#[$outer:meta])* pub struct $name:ident: $case:ident + $repr:ty {
        $($(#[$inner:ident $($args:tt)*])* const $variant:ident = $value:expr;)*
    }) => { ... };
    ($(#[$outer:meta])* struct $name:ident: $case:ident + $repr:ty {
        $($(#[$inner:ident $($args:tt)*])* const $variant:ident = $value:expr;)*
    }) => { ... };
}

Defines an option set type.