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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.
struct Fat<Sized? T> {
f1: int,
f2: &'static str,
ptr: T
}
#[deriving(PartialEq,Eq)]
struct Bar;
#[deriving(PartialEq,Eq)]
struct Bar1 {
f: int
}
trait ToBar {
fn to_bar(&self) -> Bar;
fn to_val(&self) -> int;
}
impl ToBar for Bar {
fn to_bar(&self) -> Bar {
*self
}
fn to_val(&self) -> int {
0
}
}
impl ToBar for Bar1 {
fn to_bar(&self) -> Bar {
Bar
}
fn to_val(&self) -> int {
self.f
}
}
// x is a fat pointer
fn foo(x: &Fat<ToBar>) {
assert!(x.f1 == 5);
assert!(x.f2 == "some str");
assert!(x.ptr.to_bar() == Bar);
assert!(x.ptr.to_val() == 42);
let y = &x.ptr;
assert!(y.to_bar() == Bar);
assert!(y.to_val() == 42);
}
fn bar(x: &ToBar) {
assert!(x.to_bar() == Bar);
assert!(x.to_val() == 42);
}
fn baz(x: &Fat<Fat<ToBar>>) {
assert!(x.f1 == 5);
assert!(x.f2 == "some str");
assert!(x.ptr.f1 == 8);
assert!(x.ptr.f2 == "deep str");
assert!(x.ptr.ptr.to_bar() == Bar);
assert!(x.ptr.ptr.to_val() == 42);
let y = &x.ptr.ptr;
assert!(y.to_bar() == Bar);
assert!(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!(f6.ptr.to_bar() == Bar);
// &*
let f7: Box<ToBar> = box 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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