error[E0382]: use of moved value: `foo` --> $DIR/as-ref-2.rs:10:14 | LL | let foo = Some(Struct); | --- move occurs because `foo` has type `Option`, which does not implement the `Copy` trait LL | let _x: Option = foo.map(|s| bar(&s)); | --- ---------------- `foo` moved due to this method call | | | help: consider calling `.as_ref()` or `.as_mut()` to borrow the type's contents LL | let _y = foo; | ^^^ value used here after move | note: `Option::::map` takes ownership of the receiver `self`, which moves `foo` --> $SRC_DIR/core/src/option.rs:LL:COL error: aborting due to previous error For more information about this error, try `rustc --explain E0382`.