{"ast_node_type":"function","tokens":[{"end":76,"kind":"keyword","start":0,"text":"pub"}]}
    pub fn get_unused_rule(&self, rule_i: usize) -> Option<(&Ident, Span)> {
impl MacroRulesMacroExpander {
        // If the rhs contains an invocation like `compile_error!`, don't report it as unused.