rust/src/test/run-pass/hrtb-fn-like-trait-object.rs
Alex Crichton ec7c800d2f Remove pretty-expanded from failing tests
This commit removes pretty-expanded from all tests that wind up calling panic!
one way or another now that its internals are unstable.
2015-04-08 17:21:34 -07:00

37 lines
918 B
Rust

// 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.
// A basic test of using a higher-ranked trait bound.
trait FnLike<A,R> {
fn call(&self, arg: A) -> R;
}
type FnObject<'b> = for<'a> FnLike<&'a isize, &'a isize> + 'b;
struct Identity;
impl<'a, T> FnLike<&'a T, &'a T> for Identity {
fn call(&self, arg: &'a T) -> &'a T {
arg
}
}
fn call_repeatedly(f: &FnObject) {
let x = 3;
let y = f.call(&x);
assert_eq!(3, *y);
}
fn main() {
call_repeatedly(&Identity);
}