1error[E0277]: expected a `FnOnce<()>` closure, found `{integer}`
2  --> $DIR/closure-expected.rs:3:23
3   |
4LL |     let y = x.or_else(4);
5   |               ------- ^ expected an `FnOnce<()>` closure, found `{integer}`
6   |               |
7   |               required by a bound introduced by this call
8   |
9   = help: the trait `FnOnce<()>` is not implemented for `{integer}`
10   = note: wrap the `{integer}` in a closure with no arguments: `|| { /* code */ }`
11note: required by a bound in `Option::<T>::or_else`
12  --> $SRC_DIR/core/src/option.rs:LL:COL
13   |
14LL |     pub fn or_else<F: FnOnce() -> Option<T>>(self, f: F) -> Option<T> {
15   |                       ^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Option::<T>::or_else`
16
17error: aborting due to previous error
18
19For more information about this error, try `rustc --explain E0277`.
20