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19 lines
334 B
Rust
19 lines
334 B
Rust
//@ run-pass
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#![feature(unboxed_closures)]
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#![feature(fn_traits)]
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struct Fun<F>(F);
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impl<F, T> FnOnce<(T,)> for Fun<F> where F: Fn(T) -> T {
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type Output = T;
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extern "rust-call" fn call_once(self, (t,): (T,)) -> T {
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(self.0)(t)
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}
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}
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fn main() {
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let fun = Fun(|i: isize| i * 2);
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println!("{}", fun(3));
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}
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