33 lines
417 B
Rust
33 lines
417 B
Rust
#![feature(box_syntax)]
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trait T {
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fn print(&self);
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}
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#[derive(Debug)]
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struct S {
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#[allow(dead_code)]
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s: isize,
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}
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impl T for S {
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fn print(&self) {
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println!("{:?}", self);
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}
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}
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fn print_t(t: &dyn T) {
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t.print();
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}
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fn print_s(s: &S) {
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s.print();
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}
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pub fn main() {
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let s: Box<S> = box S { s: 5 };
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print_s(&*s);
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let t: Box<dyn T> = s as Box<dyn T>;
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print_t(&*t);
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}
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