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