17 lines
253 B
Rust
17 lines
253 B
Rust
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macro_rules! test {
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(
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fn fun() -> Option<Box<$t:ty>>;
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) => {
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fn fun(x: $t) -> Option<Box<$t>>
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{ Some(Box::new(x)) }
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}
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}
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test! {
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fn fun() -> Option<Box<i32>>;
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}
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fn main() {
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println!("{}", fun(0).unwrap());
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}
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