23 lines
481 B
Rust
23 lines
481 B
Rust
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// Contravariant with respect to a region:
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//
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// You can upcast to a *smaller region* but not a larger one. This is
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// the normal case.
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struct contravariant {
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f: fn@() -> &self/int;
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}
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fn to_same_lifetime(bi: contravariant/&r) {
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let bj: contravariant/&r = bi;
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}
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fn to_shorter_lifetime(bi: contravariant/&r) {
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let bj: contravariant/&blk = bi;
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}
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fn to_longer_lifetime(bi: contravariant/&r) -> contravariant/&static {
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bi //~ ERROR mismatched types
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}
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fn main() {
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}
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