Struct Id 

pub struct Id(/* private fields */);

Per-collection document identifier.

Wraps a NonZeroU64 so the on-disk value 0 is unambiguously “no id”. Allocated by the catalog (M5 issue #38) via Catalog::next_id — see that method for the full transactional contract.

Id implements serde::Serialize + Deserialize + MaxSize so it can appear in user Document types directly, including inside a Vec<Id> or a nested struct. The serde encoding is the inner NonZeroU64 — postcard varint-encodes it, and the deserializer rejects the on-the-wire value 0 because NonZeroU64’s serde impl already does the validation.

Implementations

impl Id

pub const fn try_new(raw: u64) -> Option<Self>

Construct an Id from a raw u64. Returns None if raw is 0 (per the sentinel-zero contract).

pub const fn from_nonzero(nz: NonZeroU64) -> Self

Total-function constructor: builds an Id from a NonZeroU64 that the caller already proved is non-zero. Use try_new at runtime boundaries.

pub const fn get(self) -> u64

The underlying u64. Always non-zero.

pub const fn as_nonzero(self) -> NonZeroU64

The underlying NonZeroU64.

pub const fn to_be_bytes(self) -> [u8; 8]

Big-endian byte encoding used as a key in a collection’s primary B-tree. The big-endian shape makes lexicographic byte comparison agree with numeric < on the underlying u64 — the documented convention from docs/format.md § Key and value encoding.

pub fn from_be_bytes(bytes: &[u8]) -> Option<Self>

Decode a big-endian Id from bytes. Returns None if the byte slice is the wrong length or names the sentinel zero.

Trait Implementations

impl Clone for Id

fn clone(&self) -> Id

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Id

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Id

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for Id

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 MaxSize for Id

const POSTCARD_MAX_SIZE: usize = 10

The maximum possible size that the serialization of this type can have, in bytes.

impl Ord for Id

fn cmp(&self, other: &Id) -> 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 PartialEq for Id

fn eq(&self, other: &Id) -> 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 PartialOrd for Id

fn partial_cmp(&self, other: &Id) -> 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 Serialize for Id

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for Id

impl Eq for Id

impl StructuralPartialEq for Id