Struct wgpu::naga::UniqueArena

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

Available on wgpu_core or naga only.

An arena whose elements are guaranteed to be unique.

A UniqueArena holds a set of unique values of type T, each with an associated Span. Inserting a value returns a Handle<T>, which can be used to index the UniqueArena and obtain shared access to the T element. Access via a Handle is an array lookup - no hash lookup is necessary.

The element type must implement Eq and Hash. Insertions of equivalent elements, according to Eq, all return the same Handle.

Once inserted, elements may not be mutated.

UniqueArena is similar to Arena: If Arena is vector-like, UniqueArena is HashSet-like.

Implementations

impl<T> UniqueArena<T>

pub fn new() -> UniqueArena<T>

Available on wgpu_core only.

Create a new arena with no initial capacity allocated.

pub fn len(&self) -> usize

Available on wgpu_core only.

Return the current number of items stored in this arena.

pub fn is_empty(&self) -> bool

Available on wgpu_core only.

Return true if the arena contains no elements.

pub fn clear(&mut self)

Available on wgpu_core only.

Clears the arena, keeping all allocations.

pub fn get_span(&self, handle: Handle<T>) -> Span

Available on wgpu_core only.

Return the span associated with handle.

If a value has been inserted multiple times, the span returned is the one provided with the first insertion.

impl<T> UniqueArena<T>

where T: Eq + Hash,

pub fn iter(&self) -> impl DoubleEndedIterator

Available on wgpu_core only.

Returns an iterator over the items stored in this arena, returning both the item’s handle and a reference to it.

pub fn insert(&mut self, value: T, span: Span) -> Handle<T>

Available on wgpu_core only.

Insert a new value into the arena.

Return a Handle<T>, which can be used to index this arena to get a shared reference to the element.

If this arena already contains an element that is Eq to value, return a Handle to the existing element, and drop value.

If value is inserted into the arena, associate span with it. An element’s span can be retrieved with the get_span method.

pub fn replace(&mut self, old: Handle<T>, new: T)

Available on wgpu_core only.

Replace an old value with a new value.

Panics

• if the old value is not in the arena
• if the new value already exists in the arena

pub fn get(&self, value: &T) -> Option<Handle<T>>

Available on wgpu_core only.

Return this arena’s handle for value, if present.

If this arena already contains an element equal to value, return its handle. Otherwise, return None.

pub fn get_handle(&self, handle: Handle<T>) -> Result<&T, BadHandle>

Available on wgpu_core only.

Return this arena’s value at handle, if that is a valid handle.

pub fn check_contains_handle(&self, handle: Handle<T>) -> Result<(), BadHandle>

Available on wgpu_core only.

Assert that handle is valid for this arena.

Trait Implementations

impl<'a, T> Arbitrary<'a> for UniqueArena<T>

where T: Eq + Hash + Arbitrary<'a>,

Available on crate feature arbitrary only.

fn arbitrary(u: &mut Unstructured<'a>) -> Result<UniqueArena<T>, Error>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<UniqueArena<T>, Error>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl<T> Clone for UniqueArena<T>

where T: Clone,

fn clone(&self) -> UniqueArena<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Debug for UniqueArena<T>

where T: Debug + Eq + Hash,

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

Formats the value using the given formatter.

impl<T> Default for UniqueArena<T>

fn default() -> UniqueArena<T>

Returns the “default value” for a type.

impl<'de, T> Deserialize<'de> for UniqueArena<T>

where T: Eq + Hash + Deserialize<'de>,

Available on crate feature deserialize only.

fn deserialize<D>( deserializer: D ) -> Result<UniqueArena<T>, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<T> Index<Handle<T>> for UniqueArena<T>

type Output = T

The returned type after indexing.

fn index(&self, handle: Handle<T>) -> &T

Performs the indexing (container[index]) operation.

impl<T> Serialize for UniqueArena<T>

where T: Eq + Hash + Serialize,

Available on crate feature serialize only.

fn serialize<S>( &self, serializer: S ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.