src/test/run-pass/trait-safety-ok.rs


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// Copyright 2014 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.

// Simple smoke test that unsafe traits can be compiled etc.


unsafe trait Foo {
    fn foo(&self) -> isize;
}

unsafe impl Foo for isize {
    fn foo(&self) -> isize { *self }
}

fn take_foo<F:Foo>(f: &F) -> isize { f.foo() }

fn main() {
    let x: isize = 22;
    assert_eq!(22, take_foo(&x));
}