node_modules/uuid/README.md - devtools/devtools-frontend - Git at Google

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 # uuid [![CI](https://github.com/uuidjs/uuid/workflows/CI/badge.svg)](https://github.com/uuidjs/uuid/actions?query=workflow%3ACI) [![Browser](https://github.com/uuidjs/uuid/workflows/Browser/badge.svg)](https://github.com/uuidjs/uuid/actions/workflows/browser.yml)

 For the creation of [RFC9562](https://www.rfc-editor.org/rfc/rfc9562.html) (formerly [RFC4122](https://www.rfc-editor.org/rfc/rfc4122.html)) UUIDs

 - **Complete** - Support for all RFC9562 UUID versions
 - **Cross-platform** - Support for...
   - [Typescript](#support)
   - [Chrome, Safari, Firefox, and Edge](#support)
   - [NodeJS](#support)
   - [React Native / Expo](#react-native--expo)
 - **Secure** - Uses modern `crypto` API for random values
 - **Compact** - Zero-dependency, [tree-shakable](https://developer.mozilla.org/en-US/docs/Glossary/Tree_shaking)
 - **CLI** - [`uuid` command line](#command-line) utility

 <!-- prettier-ignore -->
 > [!NOTE]
 >
 > Starting with `uuid@12` CommonJS is no longer supported.  See [implications](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c) and [motivation](https://github.com/uuidjs/uuid/issues/881) for details.

 ## Quickstart

 **1. Install**

 ```shell
 npm install uuid
 ```

 **2. Create a UUID**

 ```javascript
 import { v4 as uuidv4 } from 'uuid';

 uuidv4(); // ⇨ '9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d'
 ```

 For timestamp UUIDs, namespace UUIDs, and other options read on ...

 ## API Summary

 |  |  |  |
 | --- | --- | --- |
 | [`uuid.NIL`](#uuidnil) | The nil UUID string (all zeros) | New in `uuid@8.3` |
 | [`uuid.MAX`](#uuidmax) | The max UUID string (all ones) | New in `uuid@9.1` |
 | [`uuid.parse()`](#uuidparsestr) | Convert UUID string to array of bytes | New in `uuid@8.3` |
 | [`uuid.stringify()`](#uuidstringifyarr-offset) | Convert array of bytes to UUID string | New in `uuid@8.3` |
 | [`uuid.v1()`](#uuidv1options-buffer-offset) | Create a version 1 (timestamp) UUID |  |
 | [`uuid.v1ToV6()`](#uuidv1tov6uuid) | Create a version 6 UUID from a version 1 UUID | New in `uuid@10` |
 | [`uuid.v3()`](#uuidv3name-namespace-buffer-offset) | Create a version 3 (namespace w/ MD5) UUID |  |
 | [`uuid.v4()`](#uuidv4options-buffer-offset) | Create a version 4 (random) UUID |  |
 | [`uuid.v5()`](#uuidv5name-namespace-buffer-offset) | Create a version 5 (namespace w/ SHA-1) UUID |  |
 | [`uuid.v6()`](#uuidv6options-buffer-offset) | Create a version 6 (timestamp, reordered) UUID | New in `uuid@10` |
 | [`uuid.v6ToV1()`](#uuidv6tov1uuid) | Create a version 1 UUID from a version 6 UUID | New in `uuid@10` |
 | [`uuid.v7()`](#uuidv7options-buffer-offset) | Create a version 7 (Unix Epoch time-based) UUID | New in `uuid@10` |
 | ~~[`uuid.v8()`](#uuidv8)~~ | "Intentionally left blank" |  |
 | [`uuid.validate()`](#uuidvalidatestr) | Test a string to see if it is a valid UUID | New in `uuid@8.3` |
 | [`uuid.version()`](#uuidversionstr) | Detect RFC version of a UUID | New in `uuid@8.3` |

 ## API

 ### uuid.NIL

 The nil UUID string (all zeros).

 Example:

 ```javascript
 import { NIL as NIL_UUID } from 'uuid';

 NIL_UUID; // ⇨ '00000000-0000-0000-0000-000000000000'
 ```

 ### uuid.MAX

 The max UUID string (all ones).

 Example:

 ```javascript
 import { MAX as MAX_UUID } from 'uuid';

 MAX_UUID; // ⇨ 'ffffffff-ffff-ffff-ffff-ffffffffffff'
 ```

 ### uuid.parse(str)

 Convert UUID string to array of bytes

 |           |                                          |
 | --------- | ---------------------------------------- |
 | `str`     | A valid UUID `String`                    |
 | _returns_ | `Uint8Array[16]`                         |
 | _throws_  | `TypeError` if `str` is not a valid UUID |

 <!-- prettier-ignore -->
 > [!NOTE]
 > Ordering of values in the byte arrays used by `parse()` and `stringify()` follows the left &Rarr; right order of hex-pairs in UUID strings. As shown in the example below.

 Example:

 ```javascript
 import { parse as uuidParse } from 'uuid';

 // Parse a UUID
 uuidParse('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨
 // Uint8Array(16) [
 //   110, 192, 189, 127,  17,
 //   192,  67, 218, 151,  94,
 //    42, 138, 217, 235, 174,
 //    11
 // ]
 ```

 ### uuid.stringify(arr[, offset])

 Convert array of bytes to UUID string

 |                |                                                                              |
 | -------------- | ---------------------------------------------------------------------------- |
 | `arr`          | `Array`-like collection of 16 values (starting from `offset`) between 0-255. |
 | [`offset` = 0] | `Number` Starting index in the Array                                         |
 | _returns_      | `String`                                                                     |
 | _throws_       | `TypeError` if a valid UUID string cannot be generated                       |

 <!-- prettier-ignore -->
 > [!NOTE]
 > Ordering of values in the byte arrays used by `parse()` and `stringify()` follows the left &Rarr; right order of hex-pairs in UUID strings. As shown in the example below.

 Example:

 ```javascript
 import { stringify as uuidStringify } from 'uuid';

 const uuidBytes = Uint8Array.of(
   0x6e,
   0xc0,
   0xbd,
   0x7f,
   0x11,
   0xc0,
   0x43,
   0xda,
   0x97,
   0x5e,
   0x2a,
   0x8a,
   0xd9,
   0xeb,
   0xae,
   0x0b
 );

 uuidStringify(uuidBytes); // ⇨ '6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'
 ```

 ### uuid.v1([options[, buffer[, offset]]])

 Create an RFC version 1 (timestamp) UUID

 |  |  |
 | --- | --- |
 | [`options`] | `Object` with one or more of the following properties: |
 | [`options.node = (random)` ] | RFC "node" field as an `Array[6]` of byte values (per 4.1.6) |
 | [`options.clockseq = (random)`] | RFC "clock sequence" as a `Number` between 0 - 0x3fff |
 | [`options.msecs = (current time)`] | RFC "timestamp" field (`Number` of milliseconds, unix epoch) |
 | [`options.nsecs = 0`] | RFC "timestamp" field (`Number` of nanoseconds to add to `msecs`, should be 0-10,000) |
 | [`options.random = (random)`] | `Array` of 16 random bytes (0-255) used to generate other fields, above |
 | [`options.rng`] | Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) |
 | [`buffer`] | `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` |
 | [`offset` = 0] | `Number` Index to start writing UUID bytes in `buffer` |
 | _returns_ | UUID `String` if no `buffer` is specified, otherwise returns `buffer` |
 | _throws_ | `Error` if more than 10M UUIDs/sec are requested |

 <!-- prettier-ignore -->
 > [!NOTE]
 > The default [node id](https://datatracker.ietf.org/doc/html/rfc9562#section-5.1) (the last 12 digits in the UUID) is generated once, randomly, on process startup, and then remains unchanged for the duration of the process.

 <!-- prettier-ignore -->
 > [!NOTE]
 > `options.random` and `options.rng` are only meaningful on the very first call to `v1()`, where they may be passed to initialize the internal `node` and `clockseq` fields.

 Example:

 ```javascript
 import { v1 as uuidv1 } from 'uuid';

 uuidv1(); // ⇨ '2c5ea4c0-4067-11e9-9b5d-ab8dfbbd4bed'
 ```

 Example using `options`:

 ```javascript
 import { v1 as uuidv1 } from 'uuid';

 const options = {
   node: Uint8Array.of(0x01, 0x23, 0x45, 0x67, 0x89, 0xab),
   clockseq: 0x1234,
   msecs: new Date('2011-11-01').getTime(),
   nsecs: 5678,
 };
 uuidv1(options); // ⇨ '710b962e-041c-11e1-9234-0123456789ab'
 ```

 ### uuid.v1ToV6(uuid)

 Convert a UUID from version 1 to version 6

 ```javascript
 import { v1ToV6 } from 'uuid';

 v1ToV6('92f62d9e-22c4-11ef-97e9-325096b39f47'); // ⇨ '1ef22c49-2f62-6d9e-97e9-325096b39f47'
 ```

 ### uuid.v3(name, namespace[, buffer[, offset]])

 Create an RFC version 3 (namespace w/ MD5) UUID

 API is identical to `v5()`, but uses "v3" instead.

 <!-- prettier-ignore -->
 > [!IMPORTANT]
 > Per the RFC, "_If backward compatibility is not an issue, SHA-1 [Version 5] is preferred_."

 ### uuid.v4([options[, buffer[, offset]]])

 Create an RFC version 4 (random) UUID

 |  |  |
 | --- | --- |
 | [`options`] | `Object` with one or more of the following properties: |
 | [`options.random`] | `Array` of 16 random bytes (0-255) |
 | [`options.rng`] | Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) |
 | [`buffer`] | `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` |
 | [`offset` = 0] | `Number` Index to start writing UUID bytes in `buffer` |
 | _returns_ | UUID `String` if no `buffer` is specified, otherwise returns `buffer` |

 Example:

 ```javascript
 import { v4 as uuidv4 } from 'uuid';

 uuidv4(); // ⇨ '1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed'
 ```

 Example using predefined `random` values:

 ```javascript
 import { v4 as uuidv4 } from 'uuid';

 const v4options = {
   random: Uint8Array.of(
     0x10,
     0x91,
     0x56,
     0xbe,
     0xc4,
     0xfb,
     0xc1,
     0xea,
     0x71,
     0xb4,
     0xef,
     0xe1,
     0x67,
     0x1c,
     0x58,
     0x36
   ),
 };
 uuidv4(v4options); // ⇨ '109156be-c4fb-41ea-b1b4-efe1671c5836'
 ```

 ### uuid.v5(name, namespace[, buffer[, offset]])

 Create an RFC version 5 (namespace w/ SHA-1) UUID

 |  |  |
 | --- | --- |
 | `name` | `String \| Array` |
 | `namespace` | `String \| Array[16]` Namespace UUID |
 | [`buffer`] | `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` |
 | [`offset` = 0] | `Number` Index to start writing UUID bytes in `buffer` |
 | _returns_ | UUID `String` if no `buffer` is specified, otherwise returns `buffer` |

 <!-- prettier-ignore -->
 > [!NOTE]
 > The RFC `DNS` and `URL` namespaces are available as `v5.DNS` and `v5.URL`.

 Example with custom namespace:

 ```javascript
 import { v5 as uuidv5 } from 'uuid';

 // Define a custom namespace.  Readers, create your own using something like
 // https://www.uuidgenerator.net/
 const MY_NAMESPACE = '1b671a64-40d5-491e-99b0-da01ff1f3341';

 uuidv5('Hello, World!', MY_NAMESPACE); // ⇨ '630eb68f-e0fa-5ecc-887a-7c7a62614681'
 ```

 Example with RFC `URL` namespace:

 ```javascript
 import { v5 as uuidv5 } from 'uuid';

 uuidv5('https://www.w3.org/', uuidv5.URL); // ⇨ 'c106a26a-21bb-5538-8bf2-57095d1976c1'
 ```

 ### uuid.v6([options[, buffer[, offset]]])

 Create an RFC version 6 (timestamp, reordered) UUID

 This method takes the same arguments as uuid.v1().

 ```javascript
 import { v6 as uuidv6 } from 'uuid';

 uuidv6(); // ⇨ '1e940672-c5ea-64c1-9bdd-2b0d7b3dcb6d'
 ```

 Example using `options`:

 ```javascript
 import { v6 as uuidv6 } from 'uuid';

 const options = {
   node: [0x01, 0x23, 0x45, 0x67, 0x89, 0xab],
   clockseq: 0x1234,
   msecs: new Date('2011-11-01').getTime(),
   nsecs: 5678,
 };
 uuidv6(options); // ⇨ '1e1041c7-10b9-662e-9234-0123456789ab'
 ```

 ### uuid.v6ToV1(uuid)

 Convert a UUID from version 6 to version 1

 ```javascript
 import { v6ToV1 } from 'uuid';

 v6ToV1('1ef22c49-2f62-6d9e-97e9-325096b39f47'); // ⇨ '92f62d9e-22c4-11ef-97e9-325096b39f47'
 ```

 ### uuid.v7([options[, buffer[, offset]]])

 Create an RFC version 7 (random) UUID

 |  |  |
 | --- | --- |
 | [`options`] | `Object` with one or more of the following properties: |
 | [`options.msecs = (current time)`] | RFC "timestamp" field (`Number` of milliseconds, unix epoch) |
 | [`options.random = (random)`] | `Array` of 16 random bytes (0-255) used to generate other fields, above |
 | [`options.rng`] | Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) |
 | [`options.seq = (random)`] | 32-bit sequence `Number` between 0 - 0xffffffff. This may be provided to help ensure uniqueness for UUIDs generated within the same millisecond time interval. Default = random value. |
 | [`buffer`] | `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` |
 | [`offset` = 0] | `Number` Index to start writing UUID bytes in `buffer` |
 | _returns_ | UUID `String` if no `buffer` is specified, otherwise returns `buffer` |

 Example:

 ```javascript
 import { v7 as uuidv7 } from 'uuid';

 uuidv7(); // ⇨ '01695553-c90c-745a-b76f-770d7b3dcb6d'
 ```

 ### ~~uuid.v8()~~

 **_"Intentionally left blank"_**

 <!-- prettier-ignore -->
 > [!NOTE]
 > Version 8 (experimental) UUIDs are "[for experimental or vendor-specific use cases](https://www.rfc-editor.org/rfc/rfc9562.html#name-uuid-version-8)".  The RFC does not define a creation algorithm for them, which is why this package does not offer a `v8()` method.  The `validate()` and `version()` methods do work with such UUIDs, however.

 ### uuid.validate(str)

 Test a string to see if it is a valid UUID

 |           |                                                     |
 | --------- | --------------------------------------------------- |
 | `str`     | `String` to validate                                |
 | _returns_ | `true` if string is a valid UUID, `false` otherwise |

 Example:

 ```javascript
 import { validate as uuidValidate } from 'uuid';

 uuidValidate('not a UUID'); // ⇨ false
 uuidValidate('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ true
 ```

 Using `validate` and `version` together it is possible to do per-version validation, e.g. validate for only v4 UUIds.

 ```javascript
 import { version as uuidVersion } from 'uuid';
 import { validate as uuidValidate } from 'uuid';

 function uuidValidateV4(uuid) {
   return uuidValidate(uuid) && uuidVersion(uuid) === 4;
 }

 const v1Uuid = 'd9428888-122b-11e1-b85c-61cd3cbb3210';
 const v4Uuid = '109156be-c4fb-41ea-b1b4-efe1671c5836';

 uuidValidateV4(v4Uuid); // ⇨ true
 uuidValidateV4(v1Uuid); // ⇨ false
 ```

 ### uuid.version(str)

 Detect RFC version of a UUID

 |           |                                          |
 | --------- | ---------------------------------------- |
 | `str`     | A valid UUID `String`                    |
 | _returns_ | `Number` The RFC version of the UUID     |
 | _throws_  | `TypeError` if `str` is not a valid UUID |

 Example:

 ```javascript
 import { version as uuidVersion } from 'uuid';

 uuidVersion('45637ec4-c85f-11ea-87d0-0242ac130003'); // ⇨ 1
 uuidVersion('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ 4
 ```

 <!-- prettier-ignore -->
 > [!NOTE]
 > This method returns `0` for the `NIL` UUID, and `15` for the `MAX` UUID.

 ## Command Line

 UUIDs can be generated from the command line using `uuid`.

 ```shell
 $ npx uuid
 ddeb27fb-d9a0-4624-be4d-4615062daed4
 ```

 The default is to generate version 4 UUIDS, however the other versions are supported. Type `uuid --help` for details:

 ```shell
 $ npx uuid --help

 Usage:
   uuid
   uuid v1
   uuid v3 <name> <namespace uuid>
   uuid v4
   uuid v5 <name> <namespace uuid>
   uuid v7
   uuid --help

 Note: <namespace uuid> may be "URL" or "DNS" to use the corresponding UUIDs
 defined by RFC9562
 ```

 ## `options` Handling for Timestamp UUIDs

 Prior to `uuid@11`, it was possible for `options` state to interfere with the internal state used to ensure uniqueness of timestamp-based UUIDs (the `v1()`, `v6()`, and `v7()` methods). Starting with `uuid@11`, this issue has been addressed by using the presence of the `options` argument as a flag to select between two possible behaviors:

 - Without `options`: Internal state is utilized to improve UUID uniqueness.
 - With `options`: Internal state is **NOT** used and, instead, appropriate defaults are applied as needed.

 ## Support

 **Browsers**: `uuid` [builds are tested](/uuidjs/uuid/blob/main/wdio.conf.js) against the latest version of desktop Chrome, Safari, Firefox, and Edge. Mobile versions of these same browsers are expected to work but aren't currently tested.

 **Node**: `uuid` [builds are tested](https://github.com/uuidjs/uuid/blob/main/.github/workflows/ci.yml#L26-L27) against node ([LTS releases](https://github.com/nodejs/Release)), plus one prior. E.g. At the time of this writing `node@20` is the "maintenance" release and `node@24` is the "current" release, so `uuid` supports `node@18`-`node@24`.

 **Typescript**: TS versions released within the past two years are supported. [source](https://github.com/microsoft/TypeScript/issues/49088#issuecomment-2468723715)

 ## Known issues

 <!-- This header is referenced as an anchor in src/rng-browser.ts -->

 ### "getRandomValues() not supported"

 This error occurs in environments where the standard [`crypto.getRandomValues()`](https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues) API is not supported. This issue can be resolved by adding an appropriate polyfill:

 #### React Native / Expo

 1. Install [`react-native-get-random-values`](https://github.com/LinusU/react-native-get-random-values#readme)
 1. Import it _before_ `uuid`. Since `uuid` might also appear as a transitive dependency of some other imports it's safest to just import `react-native-get-random-values` as the very first thing in your entry point:

 ```javascript
 import 'react-native-get-random-values';
 import { v4 as uuidv4 } from 'uuid';
 ```

 ---

 Markdown generated from [README_js.md](README_js.md) by <a href="https://github.com/broofa/runmd"><image height="13" src="https://camo.githubusercontent.com/5c7c603cd1e6a43370b0a5063d457e0dabb74cf317adc7baba183acb686ee8d0/687474703a2f2f692e696d6775722e636f6d2f634a4b6f3662552e706e67" /></a>
	<!--
	-- This file is auto-generated from README_js.md. Changes should be made there.
	-->

	# uuid [![CI](https://github.com/uuidjs/uuid/workflows/CI/badge.svg)](https://github.com/uuidjs/uuid/actions?query=workflow%3ACI) [![Browser](https://github.com/uuidjs/uuid/workflows/Browser/badge.svg)](https://github.com/uuidjs/uuid/actions/workflows/browser.yml)

	For the creation of [RFC9562](https://www.rfc-editor.org/rfc/rfc9562.html) (formerly [RFC4122](https://www.rfc-editor.org/rfc/rfc4122.html)) UUIDs

	- Complete - Support for all RFC9562 UUID versions
	- Cross-platform - Support for...
	- [Typescript](#support)
	- [Chrome, Safari, Firefox, and Edge](#support)
	- [NodeJS](#support)
	- [React Native / Expo](#react-native--expo)
	- Secure - Uses modern `crypto` API for random values
	- Compact - Zero-dependency, [tree-shakable](https://developer.mozilla.org/en-US/docs/Glossary/Tree_shaking)
	- CLI - [`uuid` command line](#command-line) utility

	<!-- prettier-ignore -->
	> [!NOTE]
	>
	> Starting with `uuid@12` CommonJS is no longer supported. See [implications](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c) and [motivation](https://github.com/uuidjs/uuid/issues/881) for details.

	## Quickstart

	1. Install

	```shell
	npm install uuid
	```

	2. Create a UUID

	```javascript
	import { v4 as uuidv4 } from 'uuid';

	uuidv4(); // ⇨ '9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d'
	```

	For timestamp UUIDs, namespace UUIDs, and other options read on ...

	## API Summary

	\| \| \| \|
	\| --- \| --- \| --- \|
	\| [`uuid.NIL`](#uuidnil) \| The nil UUID string (all zeros) \| New in `uuid@8.3` \|
	\| [`uuid.MAX`](#uuidmax) \| The max UUID string (all ones) \| New in `uuid@9.1` \|
	\| [`uuid.parse()`](#uuidparsestr) \| Convert UUID string to array of bytes \| New in `uuid@8.3` \|
	\| [`uuid.stringify()`](#uuidstringifyarr-offset) \| Convert array of bytes to UUID string \| New in `uuid@8.3` \|
	\| [`uuid.v1()`](#uuidv1options-buffer-offset) \| Create a version 1 (timestamp) UUID \| \|
	\| [`uuid.v1ToV6()`](#uuidv1tov6uuid) \| Create a version 6 UUID from a version 1 UUID \| New in `uuid@10` \|
	\| [`uuid.v3()`](#uuidv3name-namespace-buffer-offset) \| Create a version 3 (namespace w/ MD5) UUID \| \|
	\| [`uuid.v4()`](#uuidv4options-buffer-offset) \| Create a version 4 (random) UUID \| \|
	\| [`uuid.v5()`](#uuidv5name-namespace-buffer-offset) \| Create a version 5 (namespace w/ SHA-1) UUID \| \|
	\| [`uuid.v6()`](#uuidv6options-buffer-offset) \| Create a version 6 (timestamp, reordered) UUID \| New in `uuid@10` \|
	\| [`uuid.v6ToV1()`](#uuidv6tov1uuid) \| Create a version 1 UUID from a version 6 UUID \| New in `uuid@10` \|
	\| [`uuid.v7()`](#uuidv7options-buffer-offset) \| Create a version 7 (Unix Epoch time-based) UUID \| New in `uuid@10` \|
	\| ~~[`uuid.v8()`](#uuidv8)~~ \| "Intentionally left blank" \| \|
	\| [`uuid.validate()`](#uuidvalidatestr) \| Test a string to see if it is a valid UUID \| New in `uuid@8.3` \|
	\| [`uuid.version()`](#uuidversionstr) \| Detect RFC version of a UUID \| New in `uuid@8.3` \|

	## API

	### uuid.NIL

	The nil UUID string (all zeros).

	Example:

	```javascript
	import { NIL as NIL_UUID } from 'uuid';

	NIL_UUID; // ⇨ '00000000-0000-0000-0000-000000000000'
	```

	### uuid.MAX

	The max UUID string (all ones).

	Example:

	```javascript
	import { MAX as MAX_UUID } from 'uuid';

	MAX_UUID; // ⇨ 'ffffffff-ffff-ffff-ffff-ffffffffffff'
	```

	### uuid.parse(str)

	Convert UUID string to array of bytes

	\| \| \|
	\| --------- \| ---------------------------------------- \|
	\| `str` \| A valid UUID `String` \|
	\| _returns_ \| `Uint8Array[16]` \|
	\| _throws_ \| `TypeError` if `str` is not a valid UUID \|

	<!-- prettier-ignore -->
	> [!NOTE]
	> Ordering of values in the byte arrays used by `parse()` and `stringify()` follows the left &Rarr; right order of hex-pairs in UUID strings. As shown in the example below.

	Example:

	```javascript
	import { parse as uuidParse } from 'uuid';

	// Parse a UUID
	uuidParse('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨
	// Uint8Array(16) [
	// 110, 192, 189, 127, 17,
	// 192, 67, 218, 151, 94,
	// 42, 138, 217, 235, 174,
	// 11
	// ]
	```

	### uuid.stringify(arr[, offset])

	Convert array of bytes to UUID string

	\| \| \|
	\| -------------- \| ---------------------------------------------------------------------------- \|
	\| `arr` \| `Array`-like collection of 16 values (starting from `offset`) between 0-255. \|
	\| [`offset` = 0] \| `Number` Starting index in the Array \|
	\| _returns_ \| `String` \|
	\| _throws_ \| `TypeError` if a valid UUID string cannot be generated \|

	<!-- prettier-ignore -->
	> [!NOTE]
	> Ordering of values in the byte arrays used by `parse()` and `stringify()` follows the left &Rarr; right order of hex-pairs in UUID strings. As shown in the example below.

	Example:

	```javascript
	import { stringify as uuidStringify } from 'uuid';

	const uuidBytes = Uint8Array.of(
	0x6e,
	0xc0,
	0xbd,
	0x7f,
	0x11,
	0xc0,
	0x43,
	0xda,
	0x97,
	0x5e,
	0x2a,
	0x8a,
	0xd9,
	0xeb,
	0xae,
	0x0b
	);

	uuidStringify(uuidBytes); // ⇨ '6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'
	```

	### uuid.v1([options[, buffer[, offset]]])

	Create an RFC version 1 (timestamp) UUID

	\| \| \|
	\| --- \| --- \|
	\| [`options`] \| `Object` with one or more of the following properties: \|
	\| [`options.node = (random)` ] \| RFC "node" field as an `Array[6]` of byte values (per 4.1.6) \|
	\| [`options.clockseq = (random)`] \| RFC "clock sequence" as a `Number` between 0 - 0x3fff \|
	\| [`options.msecs = (current time)`] \| RFC "timestamp" field (`Number` of milliseconds, unix epoch) \|
	\| [`options.nsecs = 0`] \| RFC "timestamp" field (`Number` of nanoseconds to add to `msecs`, should be 0-10,000) \|
	\| [`options.random = (random)`] \| `Array` of 16 random bytes (0-255) used to generate other fields, above \|
	\| [`options.rng`] \| Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) \|
	\| [`buffer`] \| `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` \|
	\| [`offset` = 0] \| `Number` Index to start writing UUID bytes in `buffer` \|
	\| _returns_ \| UUID `String` if no `buffer` is specified, otherwise returns `buffer` \|
	\| _throws_ \| `Error` if more than 10M UUIDs/sec are requested \|

	<!-- prettier-ignore -->
	> [!NOTE]
	> The default [node id](https://datatracker.ietf.org/doc/html/rfc9562#section-5.1) (the last 12 digits in the UUID) is generated once, randomly, on process startup, and then remains unchanged for the duration of the process.

	<!-- prettier-ignore -->
	> [!NOTE]
	> `options.random` and `options.rng` are only meaningful on the very first call to `v1()`, where they may be passed to initialize the internal `node` and `clockseq` fields.

	Example:

	```javascript
	import { v1 as uuidv1 } from 'uuid';

	uuidv1(); // ⇨ '2c5ea4c0-4067-11e9-9b5d-ab8dfbbd4bed'
	```

	Example using `options`:

	```javascript
	import { v1 as uuidv1 } from 'uuid';

	const options = {
	node: Uint8Array.of(0x01, 0x23, 0x45, 0x67, 0x89, 0xab),
	clockseq: 0x1234,
	msecs: new Date('2011-11-01').getTime(),
	nsecs: 5678,
	};
	uuidv1(options); // ⇨ '710b962e-041c-11e1-9234-0123456789ab'
	```

	### uuid.v1ToV6(uuid)

	Convert a UUID from version 1 to version 6

	```javascript
	import { v1ToV6 } from 'uuid';

	v1ToV6('92f62d9e-22c4-11ef-97e9-325096b39f47'); // ⇨ '1ef22c49-2f62-6d9e-97e9-325096b39f47'
	```

	### uuid.v3(name, namespace[, buffer[, offset]])

	Create an RFC version 3 (namespace w/ MD5) UUID

	API is identical to `v5()`, but uses "v3" instead.

	<!-- prettier-ignore -->
	> [!IMPORTANT]
	> Per the RFC, "_If backward compatibility is not an issue, SHA-1 [Version 5] is preferred_."

	### uuid.v4([options[, buffer[, offset]]])

	Create an RFC version 4 (random) UUID

	\| \| \|
	\| --- \| --- \|
	\| [`options`] \| `Object` with one or more of the following properties: \|
	\| [`options.random`] \| `Array` of 16 random bytes (0-255) \|
	\| [`options.rng`] \| Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) \|
	\| [`buffer`] \| `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` \|
	\| [`offset` = 0] \| `Number` Index to start writing UUID bytes in `buffer` \|
	\| _returns_ \| UUID `String` if no `buffer` is specified, otherwise returns `buffer` \|

	Example:

	```javascript
	import { v4 as uuidv4 } from 'uuid';

	uuidv4(); // ⇨ '1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed'
	```

	Example using predefined `random` values:

	```javascript
	import { v4 as uuidv4 } from 'uuid';

	const v4options = {
	random: Uint8Array.of(
	0x10,
	0x91,
	0x56,
	0xbe,
	0xc4,
	0xfb,
	0xc1,
	0xea,
	0x71,
	0xb4,
	0xef,
	0xe1,
	0x67,
	0x1c,
	0x58,
	0x36
	),
	};
	uuidv4(v4options); // ⇨ '109156be-c4fb-41ea-b1b4-efe1671c5836'
	```

	### uuid.v5(name, namespace[, buffer[, offset]])

	Create an RFC version 5 (namespace w/ SHA-1) UUID

	\| \| \|
	\| --- \| --- \|
	\| `name` \| `String \\| Array` \|
	\| `namespace` \| `String \\| Array[16]` Namespace UUID \|
	\| [`buffer`] \| `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` \|
	\| [`offset` = 0] \| `Number` Index to start writing UUID bytes in `buffer` \|
	\| _returns_ \| UUID `String` if no `buffer` is specified, otherwise returns `buffer` \|

	<!-- prettier-ignore -->
	> [!NOTE]
	> The RFC `DNS` and `URL` namespaces are available as `v5.DNS` and `v5.URL`.

	Example with custom namespace:

	```javascript
	import { v5 as uuidv5 } from 'uuid';

	// Define a custom namespace. Readers, create your own using something like
	// https://www.uuidgenerator.net/
	const MY_NAMESPACE = '1b671a64-40d5-491e-99b0-da01ff1f3341';

	uuidv5('Hello, World!', MY_NAMESPACE); // ⇨ '630eb68f-e0fa-5ecc-887a-7c7a62614681'
	```

	Example with RFC `URL` namespace:

	```javascript
	import { v5 as uuidv5 } from 'uuid';

	uuidv5('https://www.w3.org/', uuidv5.URL); // ⇨ 'c106a26a-21bb-5538-8bf2-57095d1976c1'
	```

	### uuid.v6([options[, buffer[, offset]]])

	Create an RFC version 6 (timestamp, reordered) UUID

	This method takes the same arguments as uuid.v1().

	```javascript
	import { v6 as uuidv6 } from 'uuid';

	uuidv6(); // ⇨ '1e940672-c5ea-64c1-9bdd-2b0d7b3dcb6d'
	```

	Example using `options`:

	```javascript
	import { v6 as uuidv6 } from 'uuid';

	const options = {
	node: [0x01, 0x23, 0x45, 0x67, 0x89, 0xab],
	clockseq: 0x1234,
	msecs: new Date('2011-11-01').getTime(),
	nsecs: 5678,
	};
	uuidv6(options); // ⇨ '1e1041c7-10b9-662e-9234-0123456789ab'
	```

	### uuid.v6ToV1(uuid)

	Convert a UUID from version 6 to version 1

	```javascript
	import { v6ToV1 } from 'uuid';

	v6ToV1('1ef22c49-2f62-6d9e-97e9-325096b39f47'); // ⇨ '92f62d9e-22c4-11ef-97e9-325096b39f47'
	```

	### uuid.v7([options[, buffer[, offset]]])

	Create an RFC version 7 (random) UUID

	\| \| \|
	\| --- \| --- \|
	\| [`options`] \| `Object` with one or more of the following properties: \|
	\| [`options.msecs = (current time)`] \| RFC "timestamp" field (`Number` of milliseconds, unix epoch) \|
	\| [`options.random = (random)`] \| `Array` of 16 random bytes (0-255) used to generate other fields, above \|
	\| [`options.rng`] \| Alternative to `options.random`, a `Function` that returns an `Array` of 16 random bytes (0-255) \|
	\| [`options.seq = (random)`] \| 32-bit sequence `Number` between 0 - 0xffffffff. This may be provided to help ensure uniqueness for UUIDs generated within the same millisecond time interval. Default = random value. \|
	\| [`buffer`] \| `Uint8Array` or `Uint8Array` subtype (e.g. Node.js `Buffer`). If provided, binary UUID is written into the array, starting at `offset` \|
	\| [`offset` = 0] \| `Number` Index to start writing UUID bytes in `buffer` \|
	\| _returns_ \| UUID `String` if no `buffer` is specified, otherwise returns `buffer` \|

	Example:

	```javascript
	import { v7 as uuidv7 } from 'uuid';

	uuidv7(); // ⇨ '01695553-c90c-745a-b76f-770d7b3dcb6d'
	```

	### ~~uuid.v8()~~

	_"Intentionally left blank"_

	<!-- prettier-ignore -->
	> [!NOTE]
	> Version 8 (experimental) UUIDs are "[for experimental or vendor-specific use cases](https://www.rfc-editor.org/rfc/rfc9562.html#name-uuid-version-8)". The RFC does not define a creation algorithm for them, which is why this package does not offer a `v8()` method. The `validate()` and `version()` methods do work with such UUIDs, however.

	### uuid.validate(str)

	Test a string to see if it is a valid UUID

	\| \| \|
	\| --------- \| --------------------------------------------------- \|
	\| `str` \| `String` to validate \|
	\| _returns_ \| `true` if string is a valid UUID, `false` otherwise \|

	Example:

	```javascript
	import { validate as uuidValidate } from 'uuid';

	uuidValidate('not a UUID'); // ⇨ false
	uuidValidate('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ true
	```

	Using `validate` and `version` together it is possible to do per-version validation, e.g. validate for only v4 UUIds.

	```javascript
	import { version as uuidVersion } from 'uuid';
	import { validate as uuidValidate } from 'uuid';

	function uuidValidateV4(uuid) {
	return uuidValidate(uuid) && uuidVersion(uuid) === 4;
	}

	const v1Uuid = 'd9428888-122b-11e1-b85c-61cd3cbb3210';
	const v4Uuid = '109156be-c4fb-41ea-b1b4-efe1671c5836';

	uuidValidateV4(v4Uuid); // ⇨ true
	uuidValidateV4(v1Uuid); // ⇨ false
	```

	### uuid.version(str)

	Detect RFC version of a UUID

	\| \| \|
	\| --------- \| ---------------------------------------- \|
	\| `str` \| A valid UUID `String` \|
	\| _returns_ \| `Number` The RFC version of the UUID \|
	\| _throws_ \| `TypeError` if `str` is not a valid UUID \|

	Example:

	```javascript
	import { version as uuidVersion } from 'uuid';

	uuidVersion('45637ec4-c85f-11ea-87d0-0242ac130003'); // ⇨ 1
	uuidVersion('6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b'); // ⇨ 4
	```

	<!-- prettier-ignore -->
	> [!NOTE]
	> This method returns `0` for the `NIL` UUID, and `15` for the `MAX` UUID.

	## Command Line

	UUIDs can be generated from the command line using `uuid`.

	```shell
	$ npx uuid
	ddeb27fb-d9a0-4624-be4d-4615062daed4
	```

	The default is to generate version 4 UUIDS, however the other versions are supported. Type `uuid --help` for details:

	```shell
	$ npx uuid --help

	Usage:
	uuid
	uuid v1
	uuid v3 <name> <namespace uuid>
	uuid v4
	uuid v5 <name> <namespace uuid>
	uuid v7
	uuid --help

	Note: <namespace uuid> may be "URL" or "DNS" to use the corresponding UUIDs
	defined by RFC9562
	```

	## `options` Handling for Timestamp UUIDs

	Prior to `uuid@11`, it was possible for `options` state to interfere with the internal state used to ensure uniqueness of timestamp-based UUIDs (the `v1()`, `v6()`, and `v7()` methods). Starting with `uuid@11`, this issue has been addressed by using the presence of the `options` argument as a flag to select between two possible behaviors:

	- Without `options`: Internal state is utilized to improve UUID uniqueness.
	- With `options`: Internal state is NOT used and, instead, appropriate defaults are applied as needed.

	## Support

	Browsers: `uuid` [builds are tested](/uuidjs/uuid/blob/main/wdio.conf.js) against the latest version of desktop Chrome, Safari, Firefox, and Edge. Mobile versions of these same browsers are expected to work but aren't currently tested.

	Node: `uuid` [builds are tested](https://github.com/uuidjs/uuid/blob/main/.github/workflows/ci.yml#L26-L27) against node ([LTS releases](https://github.com/nodejs/Release)), plus one prior. E.g. At the time of this writing `node@20` is the "maintenance" release and `node@24` is the "current" release, so `uuid` supports `node@18`-`node@24`.

	Typescript: TS versions released within the past two years are supported. [source](https://github.com/microsoft/TypeScript/issues/49088#issuecomment-2468723715)

	## Known issues

	<!-- This header is referenced as an anchor in src/rng-browser.ts -->

	### "getRandomValues() not supported"

	This error occurs in environments where the standard [`crypto.getRandomValues()`](https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues) API is not supported. This issue can be resolved by adding an appropriate polyfill:

	#### React Native / Expo

	1. Install [`react-native-get-random-values`](https://github.com/LinusU/react-native-get-random-values#readme)
	1. Import it _before_ `uuid`. Since `uuid` might also appear as a transitive dependency of some other imports it's safest to just import `react-native-get-random-values` as the very first thing in your entry point:

	```javascript
	import 'react-native-get-random-values';
	import { v4 as uuidv4 } from 'uuid';
	```

	---

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