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// run-pass
#![feature(lang_items, unboxed_closures, fn_traits)]
use std::ops::{Fn, FnMut, FnOnce};
struct S1 {
x: i32,
y: i32,
}
impl FnMut<(i32,)> for S1 {
extern "rust-call" fn call_mut(&mut self, (z,): (i32,)) -> i32 {
self.x * self.y * z
}
}
impl FnOnce<(i32,)> for S1 {
type Output = i32;
extern "rust-call" fn call_once(mut self, args: (i32,)) -> i32 {
self.call_mut(args)
}
}
struct S2 {
x: i32,
y: i32,
}
impl Fn<(i32,)> for S2 {
extern "rust-call" fn call(&self, (z,): (i32,)) -> i32 {
self.x * self.y * z
}
}
impl FnMut<(i32,)> for S2 {
extern "rust-call" fn call_mut(&mut self, args: (i32,)) -> i32 { self.call(args) }
}
impl FnOnce<(i32,)> for S2 {
type Output = i32;
extern "rust-call" fn call_once(self, args: (i32,)) -> i32 { self.call(args) }
}
struct S3 {
x: i32,
y: i32,
}
impl FnOnce<(i32,i32)> for S3 {
type Output = i32;
extern "rust-call" fn call_once(self, (z,zz): (i32,i32)) -> i32 {
self.x * self.y * z * zz
}
}
fn main() {
let mut s = S1 {
x: 3,
y: 3,
};
let ans = s(3);
assert_eq!(ans, 27);
let s = S2 {
x: 3,
y: 3,
};
let ans = s.call((3,));
assert_eq!(ans, 27);
let s = S3 {
x: 3,
y: 3,
};
let ans = s(3, 1);
assert_eq!(ans, 27);
}
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