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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.
#![allow(unknown_features)]
#![feature(box_syntax)]
struct Fat<T: ?Sized> {
f1: isize,
f2: &'static str,
ptr: T
}
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
struct Bar;
#[derive(Copy, Clone, PartialEq, Eq)]
struct Bar1 {
f: isize
}
trait ToBar {
fn to_bar(&self) -> Bar;
fn to_val(&self) -> isize;
}
impl ToBar for Bar {
fn to_bar(&self) -> Bar {
*self
}
fn to_val(&self) -> isize {
0
}
}
impl ToBar for Bar1 {
fn to_bar(&self) -> Bar {
Bar
}
fn to_val(&self) -> isize {
self.f
}
}
// x is a fat pointer
fn foo(x: &Fat<ToBar>) {
assert_eq!(x.f1, 5);
assert_eq!(x.f2, "some str");
assert_eq!(x.ptr.to_bar(), Bar);
assert_eq!(x.ptr.to_val(), 42);
let y = &x.ptr;
assert_eq!(y.to_bar(), Bar);
assert_eq!(y.to_val(), 42);
}
fn bar(x: &ToBar) {
assert_eq!(x.to_bar(), Bar);
assert_eq!(x.to_val(), 42);
}
fn baz(x: &Fat<Fat<ToBar>>) {
assert_eq!(x.f1, 5);
assert_eq!(x.f2, "some str");
assert_eq!(x.ptr.f1, 8);
assert_eq!(x.ptr.f2, "deep str");
assert_eq!(x.ptr.ptr.to_bar(), Bar);
assert_eq!(x.ptr.ptr.to_val(), 42);
let y = &x.ptr.ptr;
assert_eq!(y.to_bar(), Bar);
assert_eq!(y.to_val(), 42);
}
pub fn main() {
let f1 = Fat { f1: 5, f2: "some str", ptr: Bar1 {f :42} };
foo(&f1);
let f2 = &f1;
foo(f2);
let f3: &Fat<ToBar> = f2;
foo(f3);
let f4: &Fat<ToBar> = &f1;
foo(f4);
let f5: &Fat<ToBar> = &Fat { f1: 5, f2: "some str", ptr: Bar1 {f :42} };
foo(f5);
// Zero size object.
let f6: &Fat<ToBar> = &Fat { f1: 5, f2: "some str", ptr: Bar };
assert_eq!(f6.ptr.to_bar(), Bar);
// &*
//
// FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
let f7: Box<ToBar> = Box::new(Bar1 {f :42});
bar(&*f7);
// Deep nesting
let f1 =
Fat { f1: 5, f2: "some str", ptr: Fat { f1: 8, f2: "deep str", ptr: Bar1 {f :42}} };
baz(&f1);
let f2 = &f1;
baz(f2);
let f3: &Fat<Fat<ToBar>> = f2;
baz(f3);
let f4: &Fat<Fat<ToBar>> = &f1;
baz(f4);
let f5: &Fat<Fat<ToBar>> =
&Fat { f1: 5, f2: "some str", ptr: Fat { f1: 8, f2: "deep str", ptr: Bar1 {f :42}} };
baz(f5);
}
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