Struct valence::UniqueId

pub struct UniqueId(pub Uuid);

The universally unique identifier of an entity. Component wrapper for a Uuid.

This component is expected to remain unique and constant during the lifetime of the entity. The Default impl generates a new random UUID.

Tuple Fields

0: Uuid

Methods from Deref<Target = Uuid>

pub fn as_hyphenated(&self) -> &Hyphenated

Get a borrowed Hyphenated formatter.

pub fn as_simple(&self) -> &Simple

Get a borrowed Simple formatter.

pub fn as_urn(&self) -> &Urn

Get a borrowed Urn formatter.

pub fn as_braced(&self) -> &Braced

Get a borrowed Braced formatter.

pub const NAMESPACE_DNS: Uuid = _

pub const NAMESPACE_OID: Uuid = _

pub const NAMESPACE_URL: Uuid = _

pub const NAMESPACE_X500: Uuid = _

pub fn get_variant(&self) -> Variant

Returns the variant of the UUID structure.

This determines the interpretation of the structure of the UUID. This method simply reads the value of the variant byte. It doesn’t validate the rest of the UUID as conforming to that variant.

Examples

Basic usage:

let my_uuid = Uuid::parse_str("02f09a3f-1624-3b1d-8409-44eff7708208")?;

assert_eq!(Variant::RFC4122, my_uuid.get_variant());

References

• Variant Field in RFC 9562

pub fn get_version_num(&self) -> usize

Returns the version number of the UUID.

This represents the algorithm used to generate the value. This method is the future-proof alternative to Uuid::get_version.

Examples

Basic usage:

let my_uuid = Uuid::parse_str("02f09a3f-1624-3b1d-8409-44eff7708208")?;

assert_eq!(3, my_uuid.get_version_num());

References

• Version Field in RFC 9562

pub fn get_version(&self) -> Option<Version>

Returns the version of the UUID.

This represents the algorithm used to generate the value. If the version field doesn’t contain a recognized version then None is returned. If you’re trying to read the version for a future extension you can also use Uuid::get_version_num to unconditionally return a number. Future extensions may start to return Some once they’re standardized and supported.

Examples

Basic usage:

let my_uuid = Uuid::parse_str("02f09a3f-1624-3b1d-8409-44eff7708208")?;

assert_eq!(Some(Version::Md5), my_uuid.get_version());

References

• Version Field in RFC 9562

pub fn as_fields(&self) -> (u32, u16, u16, &[u8; 8])

Returns the four field values of the UUID.

These values can be passed to the Uuid::from_fields method to get the original Uuid back.

• The first field value represents the first group of (eight) hex digits, taken as a big-endian u32 value. For V1 UUIDs, this field represents the low 32 bits of the timestamp.
• The second field value represents the second group of (four) hex digits, taken as a big-endian u16 value. For V1 UUIDs, this field represents the middle 16 bits of the timestamp.
• The third field value represents the third group of (four) hex digits, taken as a big-endian u16 value. The 4 most significant bits give the UUID version, and for V1 UUIDs, the last 12 bits represent the high 12 bits of the timestamp.
• The last field value represents the last two groups of four and twelve hex digits, taken in order. The first 1-3 bits of this indicate the UUID variant, and for V1 UUIDs, the next 13-15 bits indicate the clock sequence and the last 48 bits indicate the node ID.

Examples

let uuid = Uuid::nil();

assert_eq!(uuid.as_fields(), (0, 0, 0, &[0u8; 8]));

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;

assert_eq!(
    uuid.as_fields(),
    (
        0xa1a2a3a4,
        0xb1b2,
        0xc1c2,
        &[0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8],
    )
);

pub fn to_fields_le(&self) -> (u32, u16, u16, &[u8; 8])

Returns the four field values of the UUID in little-endian order.

The bytes in the returned integer fields will be converted from big-endian order. This is based on the endianness of the UUID, rather than the target environment so bytes will be flipped on both big and little endian machines.

Examples

use uuid::Uuid;

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;

assert_eq!(
    uuid.to_fields_le(),
    (
        0xa4a3a2a1,
        0xb2b1,
        0xc2c1,
        &[0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8],
    )
);

pub fn as_u128(&self) -> u128

Returns a 128bit value containing the value.

The bytes in the UUID will be packed directly into a u128.

Examples

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;

assert_eq!(
    uuid.as_u128(),
    0xa1a2a3a4b1b2c1c2d1d2d3d4d5d6d7d8,
);

pub fn to_u128_le(&self) -> u128

Returns a 128bit little-endian value containing the value.

The bytes in the u128 will be flipped to convert into big-endian order. This is based on the endianness of the UUID, rather than the target environment so bytes will be flipped on both big and little endian machines.

Note that this will produce a different result than Uuid::to_fields_le, because the entire UUID is reversed, rather than reversing the individual fields in-place.

Examples

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;

assert_eq!(
    uuid.to_u128_le(),
    0xd8d7d6d5d4d3d2d1c2c1b2b1a4a3a2a1,
);

pub fn as_u64_pair(&self) -> (u64, u64)

Returns two 64bit values containing the value.

The bytes in the UUID will be split into two u64. The first u64 represents the 64 most significant bits, the second one represents the 64 least significant.

Examples

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;
assert_eq!(
    uuid.as_u64_pair(),
    (0xa1a2a3a4b1b2c1c2, 0xd1d2d3d4d5d6d7d8),
);

pub fn as_bytes(&self) -> &[u8; 16]

Returns a slice of 16 octets containing the value.

This method borrows the underlying byte value of the UUID.

Examples

let bytes1 = [
    0xa1, 0xa2, 0xa3, 0xa4,
    0xb1, 0xb2,
    0xc1, 0xc2,
    0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8,
];
let uuid1 = Uuid::from_bytes_ref(&bytes1);

let bytes2 = uuid1.as_bytes();
let uuid2 = Uuid::from_bytes_ref(bytes2);

assert_eq!(uuid1, uuid2);

assert!(std::ptr::eq(
    uuid2 as *const Uuid as *const u8,
    &bytes1 as *const [u8; 16] as *const u8,
));

pub fn to_bytes_le(&self) -> [u8; 16]

Returns the bytes of the UUID in little-endian order.

The bytes will be flipped to convert into little-endian order. This is based on the endianness of the UUID, rather than the target environment so bytes will be flipped on both big and little endian machines.

Examples

use uuid::Uuid;

let uuid = Uuid::parse_str("a1a2a3a4-b1b2-c1c2-d1d2-d3d4d5d6d7d8")?;

assert_eq!(
    uuid.to_bytes_le(),
    ([
        0xa4, 0xa3, 0xa2, 0xa1, 0xb2, 0xb1, 0xc2, 0xc1, 0xd1, 0xd2,
        0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8
    ])
);

pub fn is_nil(&self) -> bool

Tests if the UUID is nil (all zeros).

pub fn is_max(&self) -> bool

Tests if the UUID is max (all ones).

pub fn get_timestamp(&self) -> Option<Timestamp>

If the UUID is the correct version (v1, v6, or v7) this will return the timestamp in a version-agnostic Timestamp. For other versions this will return None.

Roundtripping

This method is unlikely to roundtrip a timestamp in a UUID due to the way UUIDs encode timestamps. The timestamp returned from this method will be truncated to 100ns precision for version 1 and 6 UUIDs, and to millisecond precision for version 7 UUIDs.

pub fn get_node_id(&self) -> Option<[u8; 6]>

If the UUID is the correct version (v1, or v6) this will return the node value as a 6-byte array. For other versions this will return None.

Trait Implementations

impl Clone for UniqueId

fn clone(&self) -> UniqueId

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Component for UniqueId

where UniqueId: Send + Sync + 'static,

const STORAGE_TYPE: StorageType = bevy_ecs::component::StorageType::Table

A constant indicating the storage type used for this component.

fn register_component_hooks(_hooks: &mut ComponentHooks)

Called when registering this component, allowing mutable access to its ComponentHooks.

impl Debug for UniqueId

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

Formats the value using the given formatter.

impl Default for UniqueId

Generates a new random UUID.

fn default() -> UniqueId

Returns the “default value” for a type.

impl Deref for UniqueId

type Target = Uuid

The resulting type after dereferencing.

fn deref(&self) -> &<UniqueId as Deref>::Target

Dereferences the value.

impl Hash for UniqueId

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

where __H: Hasher,

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 Ord for UniqueId

fn cmp(&self, other: &UniqueId) -> 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 + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for UniqueId

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd for UniqueId

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

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl Copy for UniqueId

impl Eq for UniqueId

impl StructuralPartialEq for UniqueId