New macro system and stdlib additions

orchid-std/src/macros/rule/state.rs

@@ -54,6 +54,9 @@ impl<'a> MatchState<'a> {
 	pub fn from_name(name: Sym, location: Pos) -> Self {
 		Self { name_posv: HashMap::from([(name, vec![location])]), placeholders: HashMap::new() }
 	}
+	pub fn names(&self) -> impl Iterator<Item = (Sym, &[Pos])> {
+		self.name_posv.iter().map(|(sym, vec)| (sym.clone(), &vec[..]))
+	}
 	pub fn get(&self, key: &Tok<String>) -> Option<&StateEntry<'a>> { self.placeholders.get(key) }
 	pub fn remove(&mut self, name: Tok<String>) -> Option<StateEntry<'a>> {
 		self.placeholders.remove(&name)