Struct PhantomData 

pub struct PhantomData<T: ?Sized>(/* private fields */);

Zero-sized type used to mark things that “act like” they own a T.

PhantomData is used to tell the compiler that a type uses T, even though T never appears in the struct’s fields.

Common use cases:

• Generic wrapper types that don’t directly store T
• Type-safe handles/IDs that track what they point to
• Zero-cost type-level state machines

Examples

use windjammer_runtime::marker::PhantomData;

// Type-safe buffer handle
pub struct BufferId<T> {
    id: u32,
    _phantom: PhantomData<T>,
}

// Compiler knows this BufferId is for CameraUniforms
let camera_buffer: BufferId<CameraUniforms> = BufferId {
    id: 42,
    _phantom: PhantomData,
};

Implementations

impl<T: ?Sized> PhantomData<T>

pub const fn new() -> PhantomData<T>

Creates a new PhantomData.

Trait Implementations

impl<T: Clone + ?Sized> Clone for PhantomData<T>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug + ?Sized> Debug for PhantomData<T>

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

Formats the value using the given formatter.

impl<T: Default + ?Sized> Default for PhantomData<T>

fn default() -> PhantomData<T>

Returns the “default value” for a type.

impl<T: Hash + ?Sized> Hash for PhantomData<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: Ord + ?Sized> Ord for PhantomData<T>

fn cmp(&self, other: &PhantomData<T>) -> 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.

impl<T: PartialEq + ?Sized> PartialEq for PhantomData<T>

fn eq(&self, other: &PhantomData<T>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T: PartialOrd + ?Sized> PartialOrd for PhantomData<T>

fn partial_cmp(&self, other: &PhantomData<T>) -> 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.

impl<T: Copy + ?Sized> Copy for PhantomData<T>

impl<T: Eq + ?Sized> Eq for PhantomData<T>

impl<T: ?Sized> StructuralPartialEq for PhantomData<T>