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-rw-r--r--library/alloc/src/collections/vec_deque/pair_slices.rs67
1 files changed, 0 insertions, 67 deletions
diff --git a/library/alloc/src/collections/vec_deque/pair_slices.rs b/library/alloc/src/collections/vec_deque/pair_slices.rs
deleted file mode 100644
index 6735424a3..000000000
--- a/library/alloc/src/collections/vec_deque/pair_slices.rs
+++ /dev/null
@@ -1,67 +0,0 @@
-use core::cmp::{self};
-use core::mem::replace;
-
-use crate::alloc::Allocator;
-
-use super::VecDeque;
-
-/// PairSlices pairs up equal length slice parts of two deques
-///
-/// For example, given deques "A" and "B" with the following division into slices:
-///
-/// A: [0 1 2] [3 4 5]
-/// B: [a b] [c d e]
-///
-/// It produces the following sequence of matching slices:
-///
-/// ([0 1], [a b])
-/// (\[2\], \[c\])
-/// ([3 4], [d e])
-///
-/// and the uneven remainder of either A or B is skipped.
-pub struct PairSlices<'a, 'b, T> {
- a0: &'a mut [T],
- a1: &'a mut [T],
- b0: &'b [T],
- b1: &'b [T],
-}
-
-impl<'a, 'b, T> PairSlices<'a, 'b, T> {
- pub fn from<A: Allocator>(to: &'a mut VecDeque<T, A>, from: &'b VecDeque<T, A>) -> Self {
- let (a0, a1) = to.as_mut_slices();
- let (b0, b1) = from.as_slices();
- PairSlices { a0, a1, b0, b1 }
- }
-
- pub fn has_remainder(&self) -> bool {
- !self.b0.is_empty()
- }
-
- pub fn remainder(self) -> impl Iterator<Item = &'b [T]> {
- IntoIterator::into_iter([self.b0, self.b1])
- }
-}
-
-impl<'a, 'b, T> Iterator for PairSlices<'a, 'b, T> {
- type Item = (&'a mut [T], &'b [T]);
- fn next(&mut self) -> Option<Self::Item> {
- // Get next part length
- let part = cmp::min(self.a0.len(), self.b0.len());
- if part == 0 {
- return None;
- }
- let (p0, p1) = replace(&mut self.a0, &mut []).split_at_mut(part);
- let (q0, q1) = self.b0.split_at(part);
-
- // Move a1 into a0, if it's empty (and b1, b0 the same way).
- self.a0 = p1;
- self.b0 = q1;
- if self.a0.is_empty() {
- self.a0 = replace(&mut self.a1, &mut []);
- }
- if self.b0.is_empty() {
- self.b0 = replace(&mut self.b1, &[]);
- }
- Some((p0, q0))
- }
-}