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17 lines
615 B
Rust
17 lines
615 B
Rust
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// Tests how we behave when the user attempts to mutate an immutable
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// binding that was introduced by either `ref` or `ref mut`
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// patterns.
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//
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// Such bindings cannot be made mutable via the mere addition of the
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// `mut` keyword, and thus we want to check that the compiler does not
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// suggest doing so.
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fn main() {
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let (mut one_two, mut three_four) = ((1, 2), (3, 4));
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let &mut (ref a, ref mut b) = &mut one_two;
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a = &three_four.0;
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//~^ ERROR cannot assign twice to immutable variable `a` [E0384]
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b = &mut three_four.1;
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//~^ ERROR cannot assign twice to immutable variable `b` [E0384]
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}
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