1 error[E0594]: cannot assign to `self.how_hungry` which is behind a `&` reference
2 --> $DIR/mutable-class-fields-2.rs:9:5
4 LL | pub fn eat(&self) {
5 | ----- help: consider changing this to be a mutable reference: `&mut self`
6 LL | self.how_hungry -= 5;
7 | ^^^^^^^^^^^^^^^^^^^^ `self` is a `&` reference, so the data it refers to cannot be written
9 error: aborting due to previous error
11 For more information about this error, try `rustc --explain E0594`.