Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
/*!
Math.uuid.js (v1.4)
http://www.broofa.com
mailto:robert@broofa.com
Copyright (c) 2010 Robert Kieffer
Dual licensed under the MIT and GPL licenses.
*/
/*
* Generate a random uuid.
*
* USAGE: Math.uuid(length, radix)
* length - the desired number of characters
* radix - the number of allowable values for each character.
*
* EXAMPLES:
* // No arguments - returns RFC4122, version 4 ID
* >>> Math.uuid()
* "92329D39-6F5C-4520-ABFC-AAB64544E172"
*
* // One argument - returns ID of the specified length
* >>> Math.uuid(15) // 15 character ID (default base=62)
* "VcydxgltxrVZSTV"
*
* // Two arguments - returns ID of the specified length, and radix. (Radix must be <= 62)
* >>> Math.uuid(8, 2) // 8 character ID (base=2)
* "01001010"
* >>> Math.uuid(8, 10) // 8 character ID (base=10)
* "47473046"
* >>> Math.uuid(8, 16) // 8 character ID (base=16)
* "098F4D35"
*/
(function() {
// Private array of chars to use
var CHARS = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
Math.uuid = function (len, radix) {
var chars = CHARS, uuid = [], i;
radix = radix || chars.length;
if (len) {
// Compact form
for (i = 0; i < len; i++) uuid[i] = chars[0 | Math.random()*radix];
} else {
// rfc4122, version 4 form
var r;
// rfc4122 requires these characters
uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
uuid[14] = '4';
// Fill in random data. At i==19 set the high bits of clock sequence as
// per rfc4122, sec. 4.1.5
for (i = 0; i < 36; i++) {
if (!uuid[i]) {
r = 0 | Math.random()*16;
uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
}
}
}
return uuid.join('');
};
// A more performant, but slightly bulkier, RFC4122v4 solution. We boost performance
// by minimizing calls to random()
Math.uuidFast = function() {
var chars = CHARS, uuid = new Array(36), rnd=0, r;
for (var i = 0; i < 36; i++) {
if (i==8 || i==13 || i==18 || i==23) {
uuid[i] = '-';
} else if (i==14) {
uuid[i] = '4';
} else {
if (rnd <= 0x02) rnd = 0x2000000 + (Math.random()*0x1000000)|0;
r = rnd & 0xf;
rnd = rnd >> 4;
uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
}
}
return uuid.join('');
};
// A more compact, but less performant, RFC4122v4 solution:
Math.uuidCompact = function() {
return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
return v.toString(16);
});
};
})();
@ghost

This comment has been minimized.

Copy link

@ghost ghost commented Jun 28, 2018

nice

@glatteis

This comment has been minimized.

Copy link

@glatteis glatteis commented Aug 20, 2019

Interesting that this is in the google.com source code

@kondasMajid

This comment has been minimized.

Copy link

@kondasMajid kondasMajid commented Mar 11, 2020

wow :) Good this also efficient

@aria-dev

This comment has been minimized.

Copy link

@aria-dev aria-dev commented Jun 5, 2020

Interesting that this is in the google.com source code

yeah! I was just curious of google.com's homepage source code and from there I fell into a rabbit hole. Its very interesting that even though the rest of the code is kinda minified and obfuscated, the licenses section have been clearly seperated!

@Sepremex

This comment has been minimized.

Copy link

@Sepremex Sepremex commented Sep 25, 2020

I was looking for a way to generate UUIDs, and now I'm curious about google's code... lol damUGuys

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.