{"ast_node_type":"variable","tokens":[{"end":55,"kind":"keyword","start":0,"text":"let"}]}
        let const_arg = self.parent_hir_id(anon_const);
    pub fn hir_opt_const_param_default_param_def_id(self, anon_const: HirId) -> Option<LocalDefId> {
        match self.parent_hir_node(const_arg) {