{"ast_node_type":"variable","tokens":[{"end":96,"kind":"keyword","start":0,"text":"if"}]}
                                if let ty::Dynamic(src_tty, _src_lt, ty::Dyn) = *src_tail.kind()
                                // Debug`) are in `rustc_hir_typeck`.
                                    && let ty::Dynamic(dst_tty, dst_lt, ty::Dyn) = *dst_tail.kind()