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|
enum Foo {
X, Y(usize, usize)
}
fn distinct_variant() {
let mut y = Foo::Y(1, 2);
let a = match y {
Foo::Y(ref mut a, _) => a,
Foo::X => panic!()
};
// While `a` and `b` are disjoint, borrowck doesn't know that `a` is not
// also used for the discriminant of `Foo`, which it would be if `a` was a
// reference.
let b = match y {
//~^ ERROR cannot use `y`
Foo::Y(_, ref mut b) => b,
Foo::X => panic!()
};
*a += 1;
*b += 1;
}
fn same_variant() {
let mut y = Foo::Y(1, 2);
let a = match y {
Foo::Y(ref mut a, _) => a,
Foo::X => panic!()
};
let b = match y {
//~^ ERROR cannot use `y`
Foo::Y(ref mut b, _) => b,
//~^ ERROR cannot borrow `y.0` as mutable
Foo::X => panic!()
};
*a += 1;
*b += 1;
}
fn main() {
}
|
