| #![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(); | |
| } |