I wonder if grammar based types exist.
I see types based of predicates (dependent types) and algebraic types. Maybe Antlr informally counts as that. But it only really parses and scans stuff.
@worldsendless It might be a good way to talk about macros.
@worldsendless Kind of like this
str_decl : 'string' id '=' val ';'
{
st.addVariable(Type.STRING, $id.text, $val.text);
// ...
};