// Copyright 2012 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // Note: the borrowck analysis is currently flow-insensitive. // Therefore, some of these errors are marked as spurious and could be // corrected by a simple change to the analysis. The others are // either genuine or would require more advanced changes. The latter // cases are noted. fn borrow(_v: &int) {} fn borrow_mut(_v: &mut int) {} fn cond() -> bool { fail!() } fn for_func(_f: &fn() -> bool) -> bool { fail!() } fn produce() -> T { fail!(); } fn inc(v: &mut ~int) { *v = ~(**v + 1); } fn loop_overarching_alias_mut() { // In this instance, the borrow encompasses the entire loop. let mut v = ~3; let mut x = &mut v; **x += 1; loop { borrow(v); //~ ERROR cannot borrow } } fn block_overarching_alias_mut() { // In this instance, the borrow encompasses the entire closure call. let mut v = ~3; let mut x = &mut v; for 3.times { borrow(v); //~ ERROR cannot borrow } *x = ~5; } fn loop_aliased_mut() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; loop { borrow_mut(v); //~ ERROR cannot borrow _x = &v; } } fn while_aliased_mut() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; while cond() { borrow_mut(v); //~ ERROR cannot borrow _x = &v; } } fn for_loop_aliased_mut() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; for for_func { borrow_mut(v); //~ ERROR cannot borrow _x = &v; } } fn loop_aliased_mut_break() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; loop { borrow_mut(v); _x = &v; break; } borrow_mut(v); //~ ERROR cannot borrow } fn while_aliased_mut_break() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; while cond() { borrow_mut(v); _x = &v; break; } borrow_mut(v); //~ ERROR cannot borrow } fn for_aliased_mut_break() { // In this instance, the borrow is carried through the loop. let mut v = ~3, w = ~4; let mut _x = &w; for for_func { // here we cannot be sure that `for_func` respects the break below borrow_mut(v); //~ ERROR cannot borrow _x = &v; break; } borrow_mut(v); //~ ERROR cannot borrow } fn while_aliased_mut_cond(cond: bool, cond2: bool) { let mut v = ~3, w = ~4; let mut x = &mut w; while cond { **x += 1; borrow(v); //~ ERROR cannot borrow if cond2 { x = &mut v; //~ ERROR cannot borrow } } } fn loop_break_pops_scopes<'r>(_v: &'r mut [uint], f: &fn(&'r mut uint) -> bool) { // Here we check that when you break out of an inner loop, the // borrows that go out of scope as you exit the inner loop are // removed from the bitset. while cond() { while cond() { // this borrow is limited to the scope of `r`... let r: &'r mut uint = produce(); if !f(&mut *r) { break; // ...so it is not live as exit the `while` loop here } } } } fn loop_loop_pops_scopes<'r>(_v: &'r mut [uint], f: &fn(&'r mut uint) -> bool) { // Similar to `loop_break_pops_scopes` but for the `loop` keyword while cond() { while cond() { // this borrow is limited to the scope of `r`... let r: &'r mut uint = produce(); if !f(&mut *r) { loop; // ...so it is not live as exit (and re-enter) the `while` loop here } } } } fn main() {}