rust/src/test/compile-fail/borrowck/borrowck-lend-flow-match.rs

37 lines
1.2 KiB
Rust

// Copyright 2012-2014 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.
// revisions: ast mir
//[mir]compile-flags: -Z emit-end-regions -Z borrowck-mir
#![allow(unused_variables)]
#![allow(unused_assignments)]
fn separate_arms() {
// Here both arms perform assignments, but only is illegal.
let mut x = None;
match x {
None => {
// It is ok to reassign x here, because there is in
// fact no outstanding loan of x!
x = Some(0);
}
Some(ref __isize) => {
x = Some(1); //[ast]~ ERROR cannot assign
//[mir]~^ ERROR cannot assign to `x` because it is borrowed (Ast)
//[mir]~| ERROR cannot assign to `x` because it is borrowed (Mir)
}
}
x.clone(); // just to prevent liveness warnings
}
fn main() {}