/
dst-deref-mut.rs
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/
dst-deref-mut.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.
// Test that a custom deref with a fat pointer return type does not ICE
pub struct Arr {
ptr: Box<[uint]>
}
impl Deref<[uint]> for Arr {
fn deref(&self) -> &[uint] {
fail!();
}
}
impl DerefMut<[uint]> for Arr {
fn deref_mut(&mut self) -> &mut [uint] {
&mut *self.ptr
}
}
pub fn foo(arr: &mut Arr) {
let x: &mut [uint] = &mut **arr;
assert!(x[0] == 1);
assert!(x[1] == 2);
assert!(x[2] == 3);
}
fn main() {
let mut a = Arr { ptr: box [1, 2, 3] };
foo(&mut a);
}