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