Run results for: Test UUID with optimizations

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser: Chrome 105

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
1	31987.2 Ops/sec
2	305045.8 Ops/sec
3	213334.0 Ops/sec
4	35340.3 Ops/sec
5	182922.8 Ops/sec

Tests:

1
const generateUUID = () => ([1e7] + -1e3 + -4e3 + -8e3 + -1e11).replace(/[018]/g, e => // eslint-disable-next-line no-bitwise (e ^ ((window.crypto || window.msCrypto).getRandomValues(new Uint8Array(1))[0] & (15 >> (e / 4)))).toString(16) ); generateUUID();
2
function uuid() { let uuid = "", i, random; for (i = 0; i < 32; i++) { random = (Math.random() * 16) | 0; if (i == 8 || i == 12 || i == 16 || i == 20) { uuid += "-"; } uuid += (i == 12 ? 4 : i == 16 ? (random & 3) | 8 : random).toString(16); } return uuid; } uuid();
3
function uuid1(a) { return a ? (a ^ ((Math.random() * 16) >> (a / 4))).toString(16) : ([1e7] + -1e3 + -4e3 + -8e3 + -1e11).replace(/[018]/g, uuid1); } uuid1()
4
var IDX=256, HEX=[], BUFFER; while (IDX--) HEX[IDX] = (IDX + 256).toString(16).substring(1); function v4() { var i=0, num, out=''; if (!BUFFER || ((IDX + 16) > 256)) { BUFFER = Array(i=256); while (i--) BUFFER[i] = 256 * Math.random() | 0; i = IDX = 0; } for (; i < 16; i++) { num = BUFFER[IDX + i]; if (i==6) out += HEX[num & 15 | 64]; else if (i==8) out += HEX[num & 63 | 128]; else out += HEX[num]; if (i & 1 && i > 1 && i < 11) out += '-'; } IDX++; return out; } v4();
5
const ui8a = new Uint8Array(1); var IDX=256, HEX=[], BUFFER = Array(IDX); while (IDX--) HEX[IDX] = (IDX + 256).toString(16).substring(1); function v4() { var i=0, num, out=''; if ((IDX + 16) > 256) { while (i--) BUFFER[i] = 256 * crypto.getRandomValues(ui8a)[0] | 0; i = IDX = 0; } for (; i < 16; i++) { num = BUFFER[IDX + i]; if (i==6) out += HEX[num & 15 | 64]; else if (i==8) out += HEX[num & 63 | 128]; else out += HEX[num]; if (i & 1 && i > 1 && i < 11) out += '-'; } IDX++; return out; } v4();

Run results for: Test UUID with optimizations

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