Macro lrp::grammar_map

macro_rules! grammar_map {
    ($($rule:literal -> $($($terms:literal)*)|*),*) => { ... };
    ($grammar:tt, $rule:literal -> $($($terms:literal)*)|*) => { ... };
    ($($rule:ident -> $($($terms:ident)*)|*),*) => { ... };
    ($grammar:tt, $rule:ident -> $($($terms:ident)*)|*) => { ... };
}