22 lines
578 B
Rust
22 lines
578 B
Rust
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//@ run-pass
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#![warn(unused_assignments)]
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fn main() {
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let mut a;
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// Assignment occurs left-to-right.
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// However, we emit warnings when this happens, so it is clear that this is happening.
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(a, a) = (0, 1); //~ WARN value assigned to `a` is never read
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assert_eq!(a, 1);
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// We can't always tell when a variable is being assigned to twice, which is why we don't try
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// to emit an error, which would be fallible.
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let mut x = 1;
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(*foo(&mut x), *foo(&mut x)) = (5, 6);
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assert_eq!(x, 6);
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}
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fn foo<'a>(x: &'a mut u32) -> &'a mut u32 {
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x
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}
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