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//@ run-pass
#![allow(unused_imports)]
// A model for how the `Fn` traits could work. You can implement at
// most one of `Go`, `GoMut`, or `GoOnce`, and then the others follow
// automatically.
//@ aux-build:go_trait.rs
extern crate go_trait;
use go_trait::{Go, GoMut, GoOnce, go, go_mut, go_once};
use std::rc::Rc;
use std::cell::Cell;
struct SomeGoableThing {
counter: Rc<Cell<isize>>
}
impl Go for SomeGoableThing {
fn go(&self, arg: isize) {
self.counter.set(self.counter.get() + arg);
}
}
struct SomeGoOnceableThing {
counter: Rc<Cell<isize>>
}
impl GoOnce for SomeGoOnceableThing {
fn go_once(self, arg: isize) {
self.counter.set(self.counter.get() + arg);
}
}
fn main() {
let counter = Rc::new(Cell::new(0));
let mut x = SomeGoableThing { counter: counter.clone() };
go(&x, 10);
assert_eq!(counter.get(), 10);
go_mut(&mut x, 100);
assert_eq!(counter.get(), 110);
go_once(x, 1_000);
assert_eq!(counter.get(), 1_110);
let x = SomeGoOnceableThing { counter: counter.clone() };
go_once(x, 10_000);
assert_eq!(counter.get(), 11_110);
}
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