| error[E0308]: mismatched types |
| --> $DIR/retslot-cast.rs:13:5 |
| | |
| LL | -> Option<&Iterator<Item=()>> { |
| | -------------------------- expected `Option<&dyn Iterator<Item = ()>>` because of return type |
| ... |
| LL | inner(x) |
| | ^^^^^^^^ expected trait `Iterator<Item = ()>`, found trait `Iterator<Item = ()> + Send` |
| | |
| = note: expected enum `Option<&dyn Iterator<Item = ()>>` |
| found enum `Option<&dyn Iterator<Item = ()> + Send>` |
| |
| error: aborting due to 1 previous error |
| |
| For more information about this error, try `rustc --explain E0308`. |
