src/test/ui/variance/variance-use-contravariant-struct-1.rs


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// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// Test various uses of structs with distint variances to make sure
// they permit lifetimes to be approximated as expected.


struct SomeStruct<T>(fn(T));

fn foo<'min,'max>(v: SomeStruct<&'max ()>)
                  -> SomeStruct<&'min ()>
    where 'max : 'min
{
    v //~ ERROR mismatched types
}


fn main() { }