diff options
Diffstat (limited to 'library/core/src/iter/sources/empty.rs')
| -rw-r--r-- | library/core/src/iter/sources/empty.rs | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/library/core/src/iter/sources/empty.rs b/library/core/src/iter/sources/empty.rs index 7abe01d17c9..98734c527f2 100644 --- a/library/core/src/iter/sources/empty.rs +++ b/library/core/src/iter/sources/empty.rs @@ -22,17 +22,17 @@ pub const fn empty<T>() -> Empty<T> { Empty(marker::PhantomData) } +// Newtype for use in `PhantomData` to avoid +// > error: const-stable function cannot use `#[feature(const_fn_fn_ptr_basics)]` +// in `const fn empty<T>()` above. +struct FnReturning<T>(fn() -> T); + /// An iterator that yields nothing. /// /// This `struct` is created by the [`empty()`] function. See its documentation for more. #[must_use = "iterators are lazy and do nothing unless consumed"] #[stable(feature = "iter_empty", since = "1.2.0")] -pub struct Empty<T>(marker::PhantomData<T>); - -#[stable(feature = "iter_empty_send_sync", since = "1.42.0")] -unsafe impl<T> Send for Empty<T> {} -#[stable(feature = "iter_empty_send_sync", since = "1.42.0")] -unsafe impl<T> Sync for Empty<T> {} +pub struct Empty<T>(marker::PhantomData<FnReturning<T>>); #[stable(feature = "core_impl_debug", since = "1.9.0")] impl<T> fmt::Debug for Empty<T> { |