1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Test that vec is now covariant in its argument type.
17 fn foo<'a,'b>(v1: Vec<&'a i32>, v2: Vec<&'b i32>) -> i32 {
18 bar(v1, v2).cloned().unwrap_or(0) // only type checks if we can intersect 'a and 'b
21 fn bar<'c>(v1: Vec<&'c i32>, v2: Vec<&'c i32>) -> Option<&'c i32> {
22 v1.get(0).cloned().or_else(|| v2.get(0).cloned())
28 assert_eq!(foo(vec![&x], vec![&y]), 22);
29 assert_eq!(foo(vec![&y], vec![&x]), 44);