rust/src/test/run-pass/trait-object-with-lifetime-bound.rs
Felix S. Klock II 4459a438c2 run-pass tests.
includes regression tests discovered during bootstrapping and tests of
cyclic structure that currently pass and are expected to continue
passing under the dropck rule.

(Note that all the uses of `unsafe_destructor` are just placating the
simple analysis used for that feature, which will eventually go away
once we have put the dropck through its paces.)
2015-02-11 13:51:21 +01:00

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1.0 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.
// Uncovered during work on new scoping rules for safe destructors
// as an important use case to support properly.
pub struct E<'a> {
pub f: &'a u8,
}
impl<'b> E<'b> {
pub fn m(&self) -> &'b u8 { self.f }
}
pub struct P<'c> {
pub g: &'c u8,
}
pub trait M {
fn n(&self) -> u8;
}
impl<'d> M for P<'d> {
fn n(&self) -> u8 { *self.g }
}
fn extension<'e>(x: &'e E<'e>) -> Box<M+'e> {
loop {
let p = P { g: x.m() };
return Box::new(p) as Box<M+'e>;
}
}
fn main() {
let w = E { f: &10u8 };
let o = extension(&w);
assert_eq!(o.n(), 10u8);
}