Macro succ

macro_rules! succ {
    (0, $submac:ident ! ($($rest:tt)*)) => { ... };
    (1, $submac:ident ! ($($rest:tt)*)) => { ... };
    (2, $submac:ident ! ($($rest:tt)*)) => { ... };
    (3, $submac:ident ! ($($rest:tt)*)) => { ... };
    (4, $submac:ident ! ($($rest:tt)*)) => { ... };
    (5, $submac:ident ! ($($rest:tt)*)) => { ... };
    (6, $submac:ident ! ($($rest:tt)*)) => { ... };
    (7, $submac:ident ! ($($rest:tt)*)) => { ... };
    (8, $submac:ident ! ($($rest:tt)*)) => { ... };
    (9, $submac:ident ! ($($rest:tt)*)) => { ... };
    (10, $submac:ident ! ($($rest:tt)*)) => { ... };
    (11, $submac:ident ! ($($rest:tt)*)) => { ... };
    (12, $submac:ident ! ($($rest:tt)*)) => { ... };
    (13, $submac:ident ! ($($rest:tt)*)) => { ... };
    (14, $submac:ident ! ($($rest:tt)*)) => { ... };
    (15, $submac:ident ! ($($rest:tt)*)) => { ... };
    (16, $submac:ident ! ($($rest:tt)*)) => { ... };
    (17, $submac:ident ! ($($rest:tt)*)) => { ... };
    (18, $submac:ident ! ($($rest:tt)*)) => { ... };
    (19, $submac:ident ! ($($rest:tt)*)) => { ... };
    (20, $submac:ident ! ($($rest:tt)*)) => { ... };
}