diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs index a289b0d6df401..ac096afb38af0 100644 --- a/library/core/src/slice/iter.rs +++ b/library/core/src/slice/iter.rs @@ -2175,7 +2175,7 @@ unsafe impl Sync for ChunksExactMut<'_, T> where T: Sync {} /// /// [`array_windows`]: slice::array_windows /// [slices]: slice -#[derive(Debug, Clone, Copy)] +#[derive(Debug)] #[stable(feature = "array_windows", since = "1.94.0")] #[must_use = "iterators are lazy and do nothing unless consumed"] pub struct ArrayWindows<'a, T: 'a, const N: usize> { @@ -2189,6 +2189,14 @@ impl<'a, T: 'a, const N: usize> ArrayWindows<'a, T, N> { } } +// FIXME(#26925) Remove in favor of `#[derive(Clone)]` +#[stable(feature = "array_windows", since = "1.94.0")] +impl Clone for ArrayWindows<'_, T, N> { + fn clone(&self) -> Self { + Self { v: self.v } + } +} + #[stable(feature = "array_windows", since = "1.94.0")] impl<'a, T, const N: usize> Iterator for ArrayWindows<'a, T, N> { type Item = &'a [T; N]; @@ -2224,6 +2232,14 @@ impl<'a, T, const N: usize> Iterator for ArrayWindows<'a, T, N> { fn last(self) -> Option { self.v.last_chunk() } + + unsafe fn __iterator_get_unchecked(&mut self, idx: usize) -> Self::Item { + // SAFETY: since the caller guarantees that `idx` is in bounds, + // which means that `idx` cannot overflow an `isize`, and the + // "slice" created by `cast_array` is a subslice of `self.v` + // thus is guaranteed to be valid for the lifetime `'a` of `self.v`. + unsafe { &*self.v.as_ptr().add(idx).cast_array() } + } } #[stable(feature = "array_windows", since = "1.94.0")] @@ -2252,6 +2268,22 @@ impl ExactSizeIterator for ArrayWindows<'_, T, N> { } } +#[unstable(feature = "trusted_len", issue = "37572")] +unsafe impl TrustedLen for ArrayWindows<'_, T, N> {} + +#[stable(feature = "array_windows", since = "1.94.0")] +impl FusedIterator for ArrayWindows<'_, T, N> {} + +#[doc(hidden)] +#[unstable(feature = "trusted_random_access", issue = "none")] +unsafe impl TrustedRandomAccess for ArrayWindows<'_, T, N> {} + +#[doc(hidden)] +#[unstable(feature = "trusted_random_access", issue = "none")] +unsafe impl TrustedRandomAccessNoCoerce for ArrayWindows<'_, T, N> { + const MAY_HAVE_SIDE_EFFECT: bool = false; +} + /// An iterator over a slice in (non-overlapping) chunks (`chunk_size` elements at a /// time), starting at the end of the slice. ///