Struct uuid::Uuid

pub struct Uuid { /* fields omitted */ }

A Universally Unique Identifier (UUID).

Methods

impl Uuid

pub fn nil() -> Uuid

The 'nil UUID'.

The nil UUID is special form of UUID that is specified to have all 128 bits set to zero, as defined in IETF RFC 4122 Section 4.1.7.

Examples

Basic usage:

use uuid::Uuid;

let uuid = Uuid::nil();

assert_eq!(uuid.hyphenated().to_string(),
           "00000000-0000-0000-0000-000000000000");

pub fn new(v: UuidVersion) -> Option<Uuid>

Creates a new Uuid.

Note that not all versions can be generated currently and None will be returned if the specified version cannot be generated.

To generate a random UUID (UuidVersion::Random), then the v4 feature must be enabled for this crate.

pub fn from_fields(
    d1: u32,
    d2: u16,
    d3: u16,
    d4: &[u8]
) -> Result<Uuid, ParseError>

Creates a Uuid from four field values.

Errors

This function will return an error if d4's length is not 8 bytes.

Examples

Basic usage:

use uuid::Uuid;

let d4 = [12, 3, 9, 56, 54, 43, 8, 9];

let uuid = Uuid::from_fields(42, 12, 5, &d4);
let uuid = uuid.map(|uuid| uuid.hyphenated().to_string());

let expected_uuid = Ok(String::from("0000002a-000c-0005-0c03-0938362b0809"));

assert_eq!(expected_uuid, uuid);

An invalid length:

use uuid::Uuid;
use uuid::ParseError;

let d4 = [12];

let uuid = Uuid::from_fields(42, 12, 5, &d4);

let expected_uuid = Err(ParseError::InvalidLength(1));

assert_eq!(expected_uuid, uuid);

pub fn from_bytes(b: &[u8]) -> Result<Uuid, ParseError>

Creates a Uuid using the supplied bytes.

Errors

This function will return an error if b has any length other than 16.

Examples

Basic usage:

use uuid::Uuid;

let bytes = [4, 54, 67, 12, 43, 2, 98, 76,
             32, 50, 87, 5, 1, 33, 43, 87];

let uuid = Uuid::from_bytes(&bytes);
let uuid = uuid.map(|uuid| uuid.hyphenated().to_string());

let expected_uuid = Ok(String::from("0436430c-2b02-624c-2032-570501212b57"));

assert_eq!(expected_uuid, uuid);

An incorrect number of bytes:

use uuid::Uuid;
use uuid::ParseError;

let bytes = [4, 54, 67, 12, 43, 2, 98, 76];

let uuid = Uuid::from_bytes(&bytes);

let expected_uuid = Err(ParseError::InvalidLength(8));

assert_eq!(expected_uuid, uuid);

pub fn get_variant(&self) -> Option<UuidVariant>

Returns the variant of the Uuid structure.

This determines the interpretation of the structure of the UUID. Currently only the RFC4122 variant is generated by this module.

• Variant Reference

pub fn get_version_num(&self) -> usize

Returns the version number of the Uuid.

This represents the algorithm used to generate the contents.

Currently only the Random (V4) algorithm is supported by this module. There are security and privacy implications for using older versions - see Wikipedia: Universally Unique Identifier for details.

• Version Reference

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

Returns the version of the Uuid.

This represents the algorithm used to generate the contents

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

Return an array of 16 octets containing the UUID data

Examples

use uuid::Uuid;

let uuid = Uuid::nil();
assert_eq!(uuid.as_bytes(), &[0; 16]);

let uuid = Uuid::parse_str("936DA01F9ABD4d9d80C702AF85C822A8").unwrap();
assert_eq!(uuid.as_bytes(),
           &[147, 109, 160, 31, 154, 189, 77, 157,
             128, 199, 2, 175, 133, 200, 34, 168]);

pub fn simple(&self) -> Simple

Returns a wrapper which when formatted via fmt::Display will format a string of 32 hexadecimal digits.

Examples

use uuid::Uuid;

let uuid = Uuid::nil();
assert_eq!(uuid.simple().to_string(),
           "00000000000000000000000000000000");

pub fn hyphenated(&self) -> Hyphenated

Returns a wrapper which when formatted via fmt::Display will format a string of hexadecimal digits separated into gropus with a hyphen.

Examples

use uuid::Uuid;

let uuid = Uuid::nil();
assert_eq!(uuid.hyphenated().to_string(),
           "00000000-0000-0000-0000-000000000000");

pub fn urn(&self) -> Urn

Returns a wrapper which when formatted via fmt::Display will format a string of the UUID as a full URN string.

Examples

use uuid::Uuid;

let uuid = Uuid::nil();
assert_eq!(uuid.urn().to_string(),
           "urn:uuid:00000000-0000-0000-0000-000000000000");

pub fn parse_str(input: &str) -> Result<Uuid, ParseError>

Parses a Uuid from a string of hexadecimal digits with optional hyphens.

Any of the formats generated by this module (simple, hyphenated, urn) are supported by this parsing function.

pub fn is_nil(&self) -> bool

Tests if the UUID is nil

Trait Implementations

impl Copy for Uuid

impl Clone for Uuid

fn clone(&self) -> Uuid

Returns a copy of the value.

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

Performs copy-assignment from source.

impl PartialEq for Uuid

fn eq(&self, __arg_0: &Uuid) -> bool

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

fn ne(&self, __arg_0: &Uuid) -> bool

This method tests for !=.

impl Eq for Uuid

impl PartialOrd for Uuid

fn partial_cmp(&self, __arg_0: &Uuid) -> Option<Ordering>

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

fn lt(&self, __arg_0: &Uuid) -> bool

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

fn le(&self, __arg_0: &Uuid) -> bool

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

fn gt(&self, __arg_0: &Uuid) -> bool

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

fn ge(&self, __arg_0: &Uuid) -> bool

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

impl Ord for Uuid

fn cmp(&self, __arg_0: &Uuid) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

impl Default for Uuid

fn default() -> Uuid

Returns the nil UUID, which is all zeroes

impl FromStr for Uuid

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(us: &str) -> Result<Uuid, ParseError>

Parse a hex string and interpret as a Uuid.

Accepted formats are a sequence of 32 hexadecimal characters, with or without hyphens (grouped as 8, 4, 4, 4, 12).

impl Debug for Uuid

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

Formats the value using the given formatter.

impl Display for Uuid

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

Formats the value using the given formatter.

impl Hash for Uuid

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

Feeds this value into the given [Hasher].

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

Feeds a slice of this type into the given [Hasher].