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freedom-js-support

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/** * 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 };