| // Tests that two closures cannot simultaneously have mutable |
| // access to the variable, whether that mutable access be used |
| // for direct assignment or for taking mutable ref. Issue #6801. |
| |
| #![feature(box_syntax)] |
| |
| |
| |
| |
| |
| fn to_fn_mut<F: FnMut()>(f: F) -> F { f } |
| |
| fn a() { |
| let mut x = 3; |
| let c1 = to_fn_mut(|| x = 4); |
| let c2 = to_fn_mut(|| x = 5); //~ ERROR cannot borrow `x` as mutable more than once |
| c1; |
| } |
| |
| fn set(x: &mut isize) { |
| *x = 4; |
| } |
| |
| fn b() { |
| let mut x = 3; |
| let c1 = to_fn_mut(|| set(&mut x)); |
| let c2 = to_fn_mut(|| set(&mut x)); //~ ERROR cannot borrow `x` as mutable more than once |
| c1; |
| } |
| |
| fn c() { |
| let mut x = 3; |
| let c1 = to_fn_mut(|| x = 5); |
| let c2 = to_fn_mut(|| set(&mut x)); //~ ERROR cannot borrow `x` as mutable more than once |
| c1; |
| } |
| |
| fn d() { |
| let mut x = 3; |
| let c1 = to_fn_mut(|| x = 5); |
| let c2 = to_fn_mut(|| { let _y = to_fn_mut(|| set(&mut x)); }); // (nested closure) |
| //~^ ERROR cannot borrow `x` as mutable more than once |
| c1; |
| } |
| |
| fn g() { |
| struct Foo { |
| f: Box<isize> |
| } |
| |
| let mut x: Box<_> = box Foo { f: box 3 }; |
| let c1 = to_fn_mut(|| set(&mut *x.f)); |
| let c2 = to_fn_mut(|| set(&mut *x.f)); |
| //~^ ERROR cannot borrow `x` as mutable more than once |
| c1; |
| } |
| |
| fn main() { |
| } |