{"ast_node_type":"other","tokens":[{"end":128,"kind":"keyword","start":0,"text":"//"}]}
                        //  - https://doc.rust-lang.org/reference/types/trait-object.html#r-type.trait-object.syntax-edition2018
                        //  - tests/ui/lint/unused/unused-parens-trait-obj-e2015.rs and
                        let dyn2015_exception = cx.sess().psess.edition == Edition2015