| //@ run-pass |
| #![feature(unboxed_closures, fn_traits)] |
| |
| struct S; |
| |
| impl FnMut<(i32,)> for S { |
| extern "rust-call" fn call_mut(&mut self, (x,): (i32,)) -> i32 { |
| x * x |
| } |
| } |
| |
| impl FnOnce<(i32,)> for S { |
| type Output = i32; |
| |
| extern "rust-call" fn call_once(mut self, args: (i32,)) -> i32 { self.call_mut(args) } |
| } |
| |
| fn call_it<F:FnMut(i32)->i32>(mut f: F, x: i32) -> i32 { |
| f(x) + 3 |
| } |
| |
| fn call_box(f: &mut dyn FnMut(i32) -> i32, x: i32) -> i32 { |
| f(x) + 3 |
| } |
| |
| fn main() { |
| let x = call_it(S, 1); |
| let y = call_box(&mut S, 1); |
| assert_eq!(x, 4); |
| assert_eq!(y, 4); |
| } |
