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//@ check-pass
#![crate_type = "lib"]
#![allow(internal_features)]
#![no_std]
#![no_core]
#![feature(
auto_traits,
const_trait_impl,
effects,
lang_items,
no_core,
staged_api,
unboxed_closures
)]
#![stable(feature = "minicore", since = "1.0.0")]
fn test() {
fn is_const_fn<F>(_: F)
where
F: const FnOnce<()>,
{
}
const fn foo() {}
is_const_fn(foo);
}
/// ---------------------------------------------------------------------- ///
/// Const fn trait definitions
#[const_trait]
#[lang = "fn"]
#[rustc_paren_sugar]
trait Fn<Args: Tuple>: ~const FnMut<Args> {
extern "rust-call" fn call(&self, args: Args) -> Self::Output;
}
#[const_trait]
#[lang = "fn_mut"]
#[rustc_paren_sugar]
trait FnMut<Args: Tuple>: ~const FnOnce<Args> {
extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output;
}
#[const_trait]
#[lang = "fn_once"]
#[rustc_paren_sugar]
trait FnOnce<Args: Tuple> {
#[lang = "fn_once_output"]
type Output;
extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
}
/// ---------------------------------------------------------------------- ///
/// All this other stuff needed for core. Unrelated to test.
#[lang = "destruct"]
#[const_trait]
trait Destruct {}
#[lang = "freeze"]
unsafe auto trait Freeze {}
#[lang = "drop"]
#[const_trait]
trait Drop {
fn drop(&mut self);
}
#[lang = "sized"]
trait Sized {}
#[lang = "copy"]
trait Copy {}
#[lang = "tuple_trait"]
trait Tuple {}
#[lang = "receiver"]
trait Receiver {}
impl<T: ?Sized> Receiver for &T {}
impl<T: ?Sized> Receiver for &mut T {}
|
