error: expected `,`
 --> $DIR/routes.rs:6:23
  |
6 |     let _ = routes![a b]; //~ ERROR expected `,`
  |                       ^

error: expected identifier
 --> $DIR/routes.rs:8:24
  |
8 |     let _ = routes![a::, ]; //~ ERROR expected identifier
  |                        ^

error: unexpected end of input, expected identifier
 --> $DIR/routes.rs:9:13
  |
9 |     let _ = routes![a::]; //~ ERROR expected identifier
  |             ^^^^^^^^^^^^

error: aborting due to 3 previous errors