Struct SegList 

pub struct SegList<T> { /* private fields */ }

Segmented list with cache-friendly segment sizes.

Support push() / pop() from the tail, and one-time consume all elements. It does not support random access.

Each segment’s capacity is calculated at runtime based on T’s size to fit within a cache line. (The first segment is 2 * CACHE_LINE_SIZE, the subsequent allocation use CACHE_LINE_SIZE * 4)

It’s faster than Vec when the number of items is small (1~64), because it does not re-allocate during push(). It’s slower than Vec when the number is very large (due to pointer dereference cost).

NOTE

T is allow to larger than 2 * CACHE_LINE_SIZE, in this case SegList will ensure at least 2 items in one segment. But it’s not efficient when T larger than 128B, you should consider put T into Box.

Refer to module level doc for examples.

Implementations

impl<T> SegList<T>

pub fn new() -> Self

Create a new empty SegList with one allocated segment

pub fn is_empty(&self) -> bool

Returns true if the list is empty

pub const fn segment_cap() -> usize

Get the base capacity of the first segment

pub fn len(&self) -> usize

Returns the total number of elements in the list

pub fn push(&mut self, item: T)

Push an element to the back of the list

pub fn pop(&mut self) -> Option<T>

Pop an element from the back of the list

pub fn iter(&self) -> SegListIter<'_, T>

Returns an iterator over the list

pub fn iter_rev(&self) -> SegListIter<'_, T>

Returns a reverse iterator over the list

pub fn iter_mut(&mut self) -> SegListIterMut<'_, T>

Returns a mutable iterator over the list

pub fn iter_mut_rev(&mut self) -> SegListIterMut<'_, T>

Returns a mutable reverse iterator over the list

pub fn drain(self) -> SegListDrain<T>

Returns a draining iterator that consumes the list and yields elements from head to tail

pub fn into_rev(self) -> SegListDrain<T>

Returns a draining iterator that consumes the list and yields elements from tail to head

pub fn first(&self) -> Option<&T>

Returns a reference to the first element in the list

pub fn first_mut(&self) -> Option<&T>

Returns a mut reference to the first element in the list

pub fn last(&self) -> Option<&T>

Returns a reference to the last element in the list

pub fn last_mut(&mut self) -> Option<&mut T>

Returns a mutable reference to the last element in the list

pub fn clear(&mut self)

Clear all elements from the list

Trait Implementations

impl<T: Debug> Debug for SegList<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Default for SegList<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> Drop for SegList<T>

fn drop(&mut self)

Executes the destructor for this type.

impl<T> IntoIterator for SegList<T>

type Item = T

The type of the elements being iterated over.

type IntoIter = SegListDrain<T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<T: Send> Send for SegList<T>

impl<T: Send> Sync for SegList<T>