270f0eef73
This is the kind of change that one is expected to need to make to accommodate overloaded-`box`. ---- Note that this is not *all* of the changes necessary to accommodate Issue 22181. It is merely the subset of those cases where there was already a let-binding in place that made it easy to add the necesasry type ascription. (For unnamed intermediate `Box` values, one must go down a different route; `Box::new` is the option that maximizes portability, but has potential inefficiency depending on whether the call is inlined.) ---- There is one place worth note, `run-pass/coerce-match.rs`, where I used an ugly form of `Box<_>` type ascription where I would have preferred to use `Box::new` to accommodate overloaded-`box`. I deliberately did not use `Box::new` here, because that is already done in coerce-match-calls.rs. ---- Precursor for overloaded-`box` and placement-`in`; see Issue 22181.
86 lines
1.8 KiB
Rust
86 lines
1.8 KiB
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.
|
|
|
|
// Test overloaded indexing combined with autoderef.
|
|
|
|
#![allow(unknown_features)]
|
|
#![feature(box_syntax)]
|
|
|
|
use std::ops::{Index, IndexMut};
|
|
|
|
struct Foo {
|
|
x: int,
|
|
y: int,
|
|
}
|
|
|
|
impl Index<int> for Foo {
|
|
type Output = int;
|
|
|
|
fn index(&self, z: &int) -> &int {
|
|
if *z == 0 {
|
|
&self.x
|
|
} else {
|
|
&self.y
|
|
}
|
|
}
|
|
}
|
|
|
|
impl IndexMut<int> for Foo {
|
|
fn index_mut(&mut self, z: &int) -> &mut int {
|
|
if *z == 0 {
|
|
&mut self.x
|
|
} else {
|
|
&mut self.y
|
|
}
|
|
}
|
|
}
|
|
|
|
trait Int {
|
|
fn get(self) -> int;
|
|
fn get_from_ref(&self) -> int;
|
|
fn inc(&mut self);
|
|
}
|
|
|
|
impl Int for int {
|
|
fn get(self) -> int { self }
|
|
fn get_from_ref(&self) -> int { *self }
|
|
fn inc(&mut self) { *self += 1; }
|
|
}
|
|
|
|
fn main() {
|
|
let mut f: Box<_> = box Foo {
|
|
x: 1,
|
|
y: 2,
|
|
};
|
|
|
|
assert_eq!(f[1], 2);
|
|
|
|
f[0] = 3;
|
|
|
|
assert_eq!(f[0], 3);
|
|
|
|
// Test explicit IndexMut where `f` must be autoderef:
|
|
{
|
|
let p = &mut f[1];
|
|
*p = 4;
|
|
}
|
|
|
|
// Test explicit Index where `f` must be autoderef:
|
|
{
|
|
let p = &f[1];
|
|
assert_eq!(*p, 4);
|
|
}
|
|
|
|
// Test calling methods with `&mut self`, `self, and `&self` receivers:
|
|
f[1].inc();
|
|
assert_eq!(f[1].get(), 5);
|
|
assert_eq!(f[1].get_from_ref(), 5);
|
|
}
|