mirror of https://github.com/rust-lang/rust
20 lines
345 B
Rust
20 lines
345 B
Rust
//@ run-pass
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// Tests that unary structs can be mutably borrowed.
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struct Empty;
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trait T<U> {
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fn next(&mut self) -> Option<U>;
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}
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impl T<isize> for Empty {
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fn next(&mut self) -> Option<isize> { None }
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}
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fn do_something_with(a : &mut dyn T<isize>) {
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println!("{:?}", a.next())
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}
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pub fn main() {
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do_something_with(&mut Empty);
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}
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