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//@ compile-flags: -Zpolymorphize=on -Zinline-mir=yes -Zmir-opt-level=0
#![feature(fn_traits, unboxed_closures)]
struct Foo<T>(T);
impl<T: Copy> Fn<()> for Foo<T> {
extern "C" fn call(&self, _: ()) -> T {
//~^ ERROR method `call` has an incompatible type for trait
match *self {
Foo(t) => t,
}
}
}
impl<T: Copy> FnMut<()> for Foo<T> {
extern "rust-call" fn call_mut(&mut self, _: ()) -> T {
self.call(())
}
}
impl<T: Copy> FnOnce<()> for Foo<T> {
type Output = T;
extern "rust-call" fn call_once(self, _: ()) -> T {
self.call(())
}
}
fn main() {
let t: u8 = 1;
println!("{}", Foo(t)());
}
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