32 lines
1.1 KiB
Rust
32 lines
1.1 KiB
Rust
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// Ensures the independence of each side in `binding @ subpat`
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// determine their binding modes independently of each other.
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//
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// That is, `binding` does not influence `subpat`.
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// This is important because we might want to allow `p1 @ p2`,
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// where both `p1` and `p2` are syntactically unrestricted patterns.
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// If `binding` is allowed to influence `subpat`,
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// this would create problems for the generalization aforementioned.
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#![feature(bindings_after_at)]
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//~^ WARN the feature `bindings_after_at` is incomplete and may cause the compiler to crash
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fn main() {
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struct NotCopy;
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let a @ b = &NotCopy; // OK
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let _: &NotCopy = a;
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let ref a @ b = &NotCopy; // OK
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let _: &&NotCopy = a;
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let ref a @ b = NotCopy; //~ ERROR cannot bind by-move and by-ref in the same pattern
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let ref mut a @ b = NotCopy; //~ ERROR cannot bind by-move and by-ref in the same pattern
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match Ok(NotCopy) {
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Ok(ref a @ b) | Err(ref a @ b) => {}
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//~^ ERROR cannot bind by-move and by-ref in the same pattern
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}
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match NotCopy {
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ref a @ b => {}
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//~^ ERROR cannot bind by-move and by-ref in the same pattern
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}
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}
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