error[E0308]: mismatched types
  --> $DIR/as-ref.rs:7:29
   |
LL |     opt.map(|arg| takes_ref(arg));
   |         ---       --------- ^^^ expected `&Foo`, found struct `Foo`
   |         |         |
   |         |         arguments to this function are incorrect
   |         help: consider using `as_ref` instead: `as_ref().map`
   |
note: function defined here
  --> $DIR/as-ref.rs:3:4
   |
LL | fn takes_ref(_: &Foo) {}
   |    ^^^^^^^^^ -------

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:8:39
   |
LL |     opt.and_then(|arg| Some(takes_ref(arg)));
   |         --------            --------- ^^^ expected `&Foo`, found struct `Foo`
   |         |                   |
   |         |                   arguments to this function are incorrect
   |         help: consider using `as_ref` instead: `as_ref().and_then`
   |
note: function defined here
  --> $DIR/as-ref.rs:3:4
   |
LL | fn takes_ref(_: &Foo) {}
   |    ^^^^^^^^^ -------

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:10:29
   |
LL |     opt.map(|arg| takes_ref(arg));
   |         ---       --------- ^^^ expected `&Foo`, found struct `Foo`
   |         |         |
   |         |         arguments to this function are incorrect
   |         help: consider using `as_ref` instead: `as_ref().map`
   |
note: function defined here
  --> $DIR/as-ref.rs:3:4
   |
LL | fn takes_ref(_: &Foo) {}
   |    ^^^^^^^^^ -------

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:11:37
   |
LL |     opt.and_then(|arg| Ok(takes_ref(arg)));
   |         --------          --------- ^^^ expected `&Foo`, found struct `Foo`
   |         |                 |
   |         |                 arguments to this function are incorrect
   |         help: consider using `as_ref` instead: `as_ref().and_then`
   |
note: function defined here
  --> $DIR/as-ref.rs:3:4
   |
LL | fn takes_ref(_: &Foo) {}
   |    ^^^^^^^^^ -------

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:13:29
   |
LL |     let y: Option<&usize> = x;
   |            --------------   ^
   |            |                |
   |            |                expected enum `Option`, found `&Option<usize>`
   |            |                help: you can convert from `&Option<T>` to `Option<&T>` using `.as_ref()`: `x.as_ref()`
   |            expected due to this
   |
   = note:   expected enum `Option<&usize>`
           found reference `&Option<usize>`

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:15:37
   |
LL |     let y: Result<&usize, &usize> = x;
   |            ----------------------   ^ expected enum `Result`, found reference
   |            |
   |            expected due to this
   |
   = note:   expected enum `Result<&usize, &usize>`
           found reference `&Result<usize, usize>`
help: you can convert from `&Result<T, E>` to `Result<&T, &E>` using `.as_ref()`
   |
LL |     let y: Result<&usize, &usize> = x.as_ref();
   |                                     ~~~~~~~~~~

error[E0308]: mismatched types
  --> $DIR/as-ref.rs:19:36
   |
LL |     let y: Result<&usize, usize> = x;
   |            ---------------------   ^ expected enum `Result`, found reference
   |            |
   |            expected due to this
   |
   = note:   expected enum `Result<&usize, usize>`
           found reference `&Result<usize, usize>`

error: aborting due to 7 previous errors

For more information about this error, try `rustc --explain E0308`.