Struct NotNull

pub struct NotNull<T, const A: u8, const S: bool, const V: u8>(/* private fields */);

A non-null pointer that we stole the high bits off.

T: type pointed to. V: number of bits to steal directly by masking them off. A: number of bits to steal based on the alignment requirements of T.

Implementations

impl<T: Sized, const A: u8, const S: bool, const V: u8> NotNull<T, A, S, V>

pub unsafe fn new(ptr: NonNull<T>) -> Self

Creates a new Ointer from a presumed legitimate pointer.

Safety

• T’s alignment must enable stealing A bits.
• The high bits (sign upwards) must match a stack pointer’s high bits.
• If compiling for a 64bit arch, V must be at most 25.
• If compiling for a non-64bit arch, V must be 0.

These invariants are checked with debug_assert only, hence unsafe. The usual caveats of pointers apply.

pub unsafe fn new_stealing(ptr: NonNull<T>, bits: usize) -> Self

Constructor that enables stealing bits.

Safety

Same as new

pub fn stolen(self) -> usize

Returns the stolen bits in the high pos.

pub fn steal(self, bits: usize) -> Self

Takes a value from the high bits of the provided usize and steals them from the ointer.

pub fn as_non_null(self) -> NonNull<T>

Get the pointer without the stolen bits

pub fn raw(self) -> usize

Direct access to the underlying data. The pointer it returns may not be valid.

Trait Implementations

impl<T: Sized, const A: u8, const S: bool, const V: u8> Clone for NotNull<T, A, S, V>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug, const A: u8, const S: bool, const V: u8> Debug for NotNull<T, A, S, V>

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

Formats the value using the given formatter.

impl<T, const A: u8, const S: bool, const V: u8> Hash for NotNull<T, A, S, V>

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, const A: u8, const S: bool, const V: u8> PartialEq for NotNull<T, A, S, V>

fn eq(&self, other: &Self) -> 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: Sized, const A: u8, const S: bool, const V: u8> Copy for NotNull<T, A, S, V>

impl<T, const A: u8, const S: bool, const V: u8> Eq for NotNull<T, A, S, V>