27 lines
520 B
Rust
27 lines
520 B
Rust
#![feature(fn_traits, unboxed_closures)]
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use std::{fmt, ops};
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struct Debuger<T> {
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x: T
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}
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impl<T: fmt::Debug> ops::FnOnce<(),> for Debuger<T> {
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type Output = ();
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fn call_once(self, _args: ()) {
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//~^ ERROR `call_once` has an incompatible type for trait
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//~| expected signature `extern "rust-call" fn
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//~| found signature `fn
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println!("{:?}", self.x);
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}
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}
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fn make_shower<T>(x: T) -> Debuger<T> {
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Debuger { x: x }
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}
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pub fn main() {
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let show3 = make_shower(3);
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show3();
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}
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