31 lines
483 B
Rust
31 lines
483 B
Rust
// run-pass
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#![feature(unboxed_closures, fn_traits)]
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use std::ops::FnMut;
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struct S {
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x: i32,
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y: i32,
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}
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impl FnMut<()> for S {
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extern "rust-call" fn call_mut(&mut self, (): ()) -> i32 {
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self.x * self.y
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}
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}
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impl FnOnce<()> for S {
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type Output = i32;
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extern "rust-call" fn call_once(mut self, args: ()) -> i32 { self.call_mut(args) }
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}
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fn main() {
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let mut s = S {
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x: 3,
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y: 3,
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};
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let ans = s();
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assert_eq!(ans, 9);
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}
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