src/test/ui/closures/issue-78720.stderr

   1 error: at least one trait must be specified
   2   --> $DIR/issue-78720.rs:1:16
   3    |
   4 LL | fn server() -> impl {
   5    |                ^^^^
   6
   7 error[E0412]: cannot find type `F` in this scope
   8   --> $DIR/issue-78720.rs:13:12
   9    |
  10 LL |     _func: F,
  11    |            ^
  12    |
  13   ::: $SRC_DIR/core/src/ops/function.rs:LL:COL
  14    |
  15 LL | pub trait Fn<Args>: FnMut<Args> {
  16    | ------------------------------- similarly named trait `Fn` defined here
  17    |
  18 help: a trait with a similar name exists
  19    |
  20 LL |     _func: Fn,
  21    |            ~~
  22 help: you might be missing a type parameter
  23    |
  24 LL | struct Map2<Segment2, F> {
  25    |                     +++
  26
  27 error[E0308]: mismatched types
  28   --> $DIR/issue-78720.rs:7:39
  29    |
  30 LL |     fn map2<F>(self, f: F) -> Map2<F> {}
  31    |                                       ^^ expected struct `Map2`, found `()`
  32    |
  33    = note: expected struct `Map2<F>`
  34            found unit type `()`
  35
  36 error[E0277]: the size for values of type `Self` cannot be known at compilation time
  37   --> $DIR/issue-78720.rs:7:16
  38    |
  39 LL |     fn map2<F>(self, f: F) -> Map2<F> {}
  40    |                ^^^^ doesn't have a size known at compile-time
  41    |
  42    = help: unsized fn params are gated as an unstable feature
  43 help: consider further restricting `Self`
  44    |
  45 LL |     fn map2<F>(self, f: F) -> Map2<F> where Self: Sized {}
  46    |                                       +++++++++++++++++
  47 help: function arguments must have a statically known size, borrowed types always have a known size
  48    |
  49 LL |     fn map2<F>(&self, f: F) -> Map2<F> {}
  50    |                +
  51
  52 error: aborting due to 4 previous errors
  53
  54 Some errors have detailed explanations: E0277, E0308, E0412.
  55 For more information about an error, try `rustc --explain E0277`.