struct X(usize); impl X { fn zap(&self) { //~^ HELP //~| SUGGESTION &mut self self.0 = 32; //~^ ERROR } } fn main() { let ref foo = 16; //~^ HELP *foo = 32; //~^ ERROR if let Some(ref bar) = Some(16) { //~^ HELP *bar = 32; //~^ ERROR } match 16 { ref quo => { *quo = 32; }, //~^ ERROR //~| HELP } }