2 // Elaborated version of the opening example from RFC 738. This failed
3 // to compile before variance because invariance of `Option` prevented
4 // us from approximating the lifetimes of `field1` and `field2` to a
5 // common intersection.
11 field2: Option<&'l i32>,
14 fn foo(field1: &i32, field2: Option<&i32>) -> i32 {
15 let list = List { field1: field1, field2: field2 };
16 *list.field1 + list.field2.cloned().unwrap_or(0)
23 assert_eq!(foo(&x, y.as_ref()), 25);
24 assert_eq!(foo(&x, z.as_ref()), 22);