enum Foo {
    Bar,
    Baz,
    Qux(u32),
}

fn main() {
    let a = Foo::Bar;
    let b = Foo::Baz;
    let c = Foo::Qux(100);

    if let Foo::Bar = a {
        println!("a is a foobar");
    }

    if let Foo::Bar = b {
        println!("b is foobar");
    }

    if let Foo::Qux(value) = c {
        println!("c is {}", value);
    }

    if let Foo::Qux(value @ 100) = c {
        println!("c is one hundred (value: {:?})", value);
    }
}