rust/src/test/compile-fail/issue-17263.rs
Felix S. Klock II 270f0eef73 Add : Box<_> or ::Box<_> type annotations to various places.
This is the kind of change that one is expected to need to make to
accommodate overloaded-`box`.

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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.
2015-03-03 20:29:01 +01:00

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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.
#![feature(box_syntax)]
struct Foo { a: isize, b: isize }
fn main() {
let mut x: Box<_> = box Foo { a: 1, b: 2 };
let (a, b) = (&mut x.a, &mut x.b);
//~^ ERROR cannot borrow `x` (here through borrowing `x.b`) as mutable more than once at a time
//~^^ NOTE previous borrow of `x` occurs here (through borrowing `x.a`)
let mut foo: Box<_> = box Foo { a: 1, b: 2 };
let (c, d) = (&mut foo.a, &foo.b);
//~^ ERROR cannot borrow `foo` (here through borrowing `foo.b`) as immutable
//~^^ NOTE previous borrow of `foo` occurs here (through borrowing `foo.a`)
}