freedom-js-support
Version:
Freedom Javascript Utilities
40 lines (31 loc) • 1.2 kB
JavaScript
/**
* Fast UUID generator, RFC4122 version 4 compliant.
* @author Jeff Ward (jcward.com).
* @license MIT license
* @link http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript/21963136#21963136
*/
const lut = [];
for (let i = 0; i < 256; i++) {
lut[i] = (i < 16 ? '0' : '') + (i).toString(16);
}
const generate = function () {
const d0 = Math.random() * 0xffffffff | 0;
const d1 = Math.random() * 0xffffffff | 0;
const d2 = Math.random() * 0xffffffff | 0;
const d3 = Math.random() * 0xffffffff | 0;
/* eslint-disable */
return lut[d0 & 0xff] + lut[d0 >> 8 & 0xff] + lut[d0 >> 16 & 0xff] + lut[d0 >> 24 & 0xff] + '-' +
lut[d1 & 0xff] + lut[d1 >> 8 & 0xff] + '-' + lut[d1 >> 16 & 0x0f | 0x40] + lut[d1 >> 24 & 0xff] + '-' +
lut[d2 & 0x3f | 0x80] + lut[d2 >> 8 & 0xff] + '-' + lut[d2 >> 16 & 0xff] + lut[d2 >> 24 & 0xff] +
lut[d3 & 0xff] + lut[d3 >> 8 & 0xff] + lut[d3 >> 16 & 0xff] + lut[d3 >> 24 & 0xff];
/* eslint-enable */
};
const short = function (prefix) {
prefix = prefix || '';
const uuid = generate();
return prefix + uuid.split('-')[0];
};
export default {
generate,
short
};