Struct Id 

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

A typed, stable index into an Arena.

T is the referenced type and is used only as a marker; Id<T> has the size of u32 and is Copy, Send, and Sync regardless of T. The comparison, hashing, and formatting impls are implemented manually so they never require T itself to implement them.

Implementations

impl<T> Id<T>

pub const fn from_index(index: usize) -> Self

Build an ID from an arena index.

This is the only way to construct an ID outside an arena. Prefer Arena::push so the ID is valid by construction; from_index exists for tests and deserialization paths that then rely on bounds-checked lookup.

pub const fn index(self) -> usize

The arena index this ID refers to.

Trait Implementations

impl<T> Clone for Id<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T> Copy for Id<T>

impl<T> Debug for Id<T>

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

Formats the value using the given formatter.

impl<T> Display for Id<T>

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

Formats the value using the given formatter.

impl<T> Eq for Id<T>

impl<T> Hash for Id<T>

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T> IdLike for Id<T>

fn index(self) -> usize

The arena index this ID refers to.

impl<T> Ord for Id<T>

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl<T> PartialEq for Id<T>

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<T> PartialOrd for Id<T>

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.