{"ast_node_type":"variable","tokens":[{"end":67,"kind":"keyword","start":0,"text":"if"}]}
        if let Some(c) = trait_segment.args().constraints.first() {
            self.lower_generic_args_of_path(span, trait_def_id, &[], trait_segment, Some(self_ty));
            prohibit_assoc_item_constraint(self, c, Some((trait_def_id, trait_segment, span)));