#![feature(never_type)] #![feature(exhaustive_patterns)] mod foo { pub struct SecretlyEmpty { _priv: !, } pub struct NotSoSecretlyEmpty { pub _pub: !, } } struct NotSoSecretlyEmpty { _priv: !, } enum Foo { //~^ NOTE `Foo` defined here A(foo::SecretlyEmpty), //~^ NOTE not covered B(foo::NotSoSecretlyEmpty), C(NotSoSecretlyEmpty), D(u32, u32), } fn main() { let x: Foo = Foo::D(123, 456); let Foo::D(_y, _z) = x; //~^ ERROR refutable pattern in local binding //~| `Foo::A(_)` not covered //~| NOTE `let` bindings require an "irrefutable pattern" //~| NOTE for more information //~| NOTE pattern `Foo::A(_)` is currently uninhabited //~| NOTE the matched value is of type `Foo` //~| HELP you might want to use `let else` }