error[E0507]: cannot move out of `var`, a captured variable in an `FnMut` closure --> $DIR/option-content-move2.rs:9:9 | LL | let mut var = None; | ------- captured outer variable LL | func(|| { | -- captured by this `FnMut` closure LL | // Shouldn't suggest `move ||.as_ref()` here LL | move || { | ^^^^^^^ move out of `var` occurs here LL | LL | var = Some(NotCopyable); | --- | | | variable moved due to use in closure | move occurs because `var` has type `Option`, which does not implement the `Copy` trait error: aborting due to previous error For more information about this error, try `rustc --explain E0507`.