23 lines
433 B
Rust
23 lines
433 B
Rust
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fn reproduce<T:copy>(t: T) -> fn@() -> T {
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fn@() -> T { t }
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}
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fn main() {
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// type of x is the variable X,
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// with the lower bound @mut int
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let x = @mut 3;
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// type of r is fn@() -> X
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let r = reproduce(x);
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// Requires that X be a subtype of
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// @mut int.
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let f: @mut int = r();
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// OK.
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let g: @const int = r();
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// Bad.
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let h: @int = r(); //! ERROR (values differ in mutability)
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}
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