1 // Copyright 2012 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 a type which is covariant with respect to its region
12 // parameter yields an error when used in a contravariant way.
14 // Note: see variance-regions-*.rs for the tests that check that the
15 // variance inference works in the first place.
19 struct Covariant<'a> {
20 marker: marker::PhantomData<fn(&'a ())>
23 fn use_<'short,'long>(c: Covariant<'long>,
26 _where:Option<&'short &'long ()>) {
28 // Test whether Covariant<'long> <: Covariant<'short>. Since
29 // 'short <= 'long, this would be true if the Covariant type were
30 // contravariant with respect to its parameter 'a.
32 let _: Covariant<'short> = c; //~ ERROR mismatched types