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