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// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
struct StateMachineIter<'a> {
statefn: &'a StateMachineFunc<'a>
}
type StateMachineFunc<'a> = fn(&mut StateMachineIter<'a>) -> Option<&'static str>;
impl<'a> Iterator for StateMachineIter<'a> {
type Item = &'static str;
fn next(&mut self) -> Option<&'static str> {
return (*self.statefn)(self);
}
}
fn state1(self_: &mut StateMachineIter) -> Option<&'static str> {
self_.statefn = &(state2 as StateMachineFunc);
//~^ ERROR borrowed value does not live long enough
return Some("state1");
}
fn state2(self_: &mut StateMachineIter) -> Option<(&'static str)> {
self_.statefn = &(state3 as StateMachineFunc);
//~^ ERROR borrowed value does not live long enough
return Some("state2");
}
fn state3(self_: &mut StateMachineIter) -> Option<(&'static str)> {
self_.statefn = &(finished as StateMachineFunc);
//~^ ERROR borrowed value does not live long enough
return Some("state3");
}
fn finished(_: &mut StateMachineIter) -> Option<(&'static str)> {
return None;
}
fn state_iter() -> StateMachineIter<'static> {
StateMachineIter {
statefn: &(state1 as StateMachineFunc) //~ ERROR borrowed value does not live long enough
}
}
fn main() {
let mut it = state_iter();
println!("{:?}",it.next());
println!("{:?}",it.next());
println!("{:?}",it.next());
println!("{:?}",it.next());
println!("{:?}",it.next());
}
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