gistfile1.rs

trait ToInt {
    fn to_int(&self) -> int { 666 }
}

struct A<'a> {
    a: &'a Box<int>
}

impl<'a> ToInt for A<'a> {
    fn to_int(&self) -> int { **self.a }
}

struct B<'b> {
    b: fn(&'b Box<int>) -> int
}

impl<'b> ToInt for B<'b> { }

struct C<'c> {
    a: &'c Box<int>,
    b: fn(&'c Box<int>) -> int
}

impl<'c> ToInt for C<'c> {
    fn to_int(&self) -> int { (self.b)(self.a) }
}

struct D<'d>;

impl<'d> ToInt for D<'d> { }

fn foo(foo: Box<ToInt + 'static>) { println!("foo: {}", foo.to_int()) }

fn main() {
    let a = &box 42;
    fn b(b: &Box<int>) -> int { **b * 10 }
    foo(box A { a: a }); // error
    foo(box B { b: b });
    foo(box C { a: a, b: b }); // error
    foo(box D)
}

/*
error: cannot pack type `Box<A<'_>>`, which does not fulfill `'static`, as a trait bounded by 'static
error: cannot pack type `Box<C<'_>>`, which does not fulfill `'static`, as a trait bounded by 'static
error: aborting due to 2 previous errors
*/