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// run-pass
#![allow(stable_features)]
// Test overloaded indexing combined with autoderef.
use std::ops::{Index, IndexMut};
struct Foo {
x: isize,
y: isize,
}
impl Index<isize> for Foo {
type Output = isize;
fn index(&self, z: isize) -> &isize {
if z == 0 {
&self.x
} else {
&self.y
}
}
}
impl IndexMut<isize> for Foo {
fn index_mut(&mut self, z: isize) -> &mut isize {
if z == 0 {
&mut self.x
} else {
&mut self.y
}
}
}
trait Int {
fn get(self) -> isize;
fn get_from_ref(&self) -> isize;
fn inc(&mut self);
}
impl Int for isize {
fn get(self) -> isize { self }
fn get_from_ref(&self) -> isize { *self }
fn inc(&mut self) { *self += 1; }
}
fn main() {
let mut f: Box<_> = Box::new(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);
}
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