error[E0191]: the value of the associated type `Bar` in `Foo` must be specified
  --> $DIR/associated-type-cycle.rs:6:22
   |
LL |     type Bar;
   |     -------- `Bar` defined here
...
LL | impl Foo for Box<dyn Foo> {
   |                      ^^^ help: specify the associated type: `Foo<Bar = Type>`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0191`.