error[E0425]: cannot find value `x` in this scope
  --> $DIR/ruby_style_closure.rs:13:14
   |
LL |         Some(x * 2)
   |              ^ not found in this scope

error[E0277]: expected a `FnOnce<({integer},)>` closure, found `Option<_>`
  --> $DIR/ruby_style_closure.rs:10:31
   |
LL |       let p = Some(45).and_then({
   |  ______________________--------_^
   | |                      |
   | |                      required by a bound introduced by this call
LL | |
LL | |         |x| println!("doubling {}", x);
LL | |         Some(x * 2)
   | |         -----------
LL | |
LL | |     });
   | |_____^ expected an `FnOnce<({integer},)>` closure, found `Option<_>`
   |
   = help: the trait `FnOnce<({integer},)>` is not implemented for `Option<_>`
note: required by a bound in `Option::<T>::and_then`
  --> $SRC_DIR/core/src/option.rs:LL:COL
   |
LL |         F: ~const FnOnce(T) -> Option<U>,
   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `Option::<T>::and_then`

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0277, E0425.
For more information about an error, try `rustc --explain E0277`.