20 lines
315 B
Rust
20 lines
315 B
Rust
// run-pass
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#![allow(non_camel_case_types)]
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trait double {
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fn double(self) -> usize;
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}
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impl double for usize {
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fn double(self) -> usize { self }
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}
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impl double for Box<usize> {
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fn double(self) -> usize { *self * 2 }
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}
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pub fn main() {
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let x: Box<_> = Box::new(3);
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assert_eq!(x.double(), 6);
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}
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