22 lines
426 B
Rust
22 lines
426 B
Rust
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// Covariant with respect to a region:
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//
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// You can upcast to a *larger region* but not a smaller one.
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struct covariant {
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f: fn@(x: &self/int) -> int;
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}
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fn to_same_lifetime(bi: covariant/&r) {
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let bj: covariant/&r = bi;
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}
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fn to_shorter_lifetime(bi: covariant/&r) {
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let bj: covariant/&blk = bi; //~ ERROR mismatched types
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}
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fn to_longer_lifetime(bi: covariant/&r) -> covariant/&static {
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bi
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}
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fn main() {
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}
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