Struct Deque 

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

Append-only deque which ensures the elements pushed into it never move. Allocates chunks in doubling capacities.

Implementations

impl<T> Deque<T>

pub fn new() -> Self

pub fn push(&mut self, val: T) -> &T

Append an element to the deque and return a reference to it. The element will not move after it is allocated.

pub fn len(&self) -> usize

Return the number of elements that have been appended to the deque.

pub fn is_empty(&self) -> bool

pub fn iter(&self) -> impl Iterator<Item = &T>

Iterator over every element of the deque.

pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut T>

Iterator over every element of the deque.

pub fn truncate(&mut self, len: usize)

Truncate the deque to len elements, dropping every element at index >= len and freeing fully-vacated trailing chunks. Surviving elements never move (only trailing elements/chunks are dropped), so references to them remain valid. Used by the AST arena’s AllocationScope (bump-allocator save/restore semantics, mirroring the C++ BumpPtrAllocator::pushScope/popScope, hermes/Support/Allocator.h:500).

pub fn iter_from(&self, index: usize) -> impl Iterator<Item = &T>

Iterate over the elements starting at index. Positions by chunk arithmetic (a handful of chunk-boundary comparisons; skipped elements are not walked), so iterating a suffix is O(suffix). An index at or past len() yields an empty iterator.

Trait Implementations

impl<T: Debug> Debug for Deque<T>

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

Formats the value using the given formatter.

impl<T> Default for Deque<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> HeapSize for Deque<T>

fn heap_size(&self) -> usize

Return the size of the heap allocated memory for the type, in bytes.