Macro nom::switch_sep

macro_rules! switch_sep {
    (__impl $i:expr, $separator:ident, $submac:ident!( $($args:tt)* ), $($p:pat => $subrule:ident!( $($args2:tt)* ))|* ) => { ... };
    ($i:expr, $separator:ident, $submac:ident!( $($args:tt)*), $($rest:tt)*) => { ... };
    ($i:expr, $separator:ident, $e:ident, $($rest:tt)*) => { ... };
}