Create an UUID in JavaScript

uuid.js

var buildUUID = function(bits) {
  var CHARS, i, rand, result, _i;
  CHARS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ012345678900';
  result = '';
  while (bits > 0) {
    rand = Math.floor(Math.random() * 0x100000000);
    for (i = _i = 26; _i > 0; i = _i += -6) {
      result += CHARS[0x3F & rand >>> i];
      bits -= 6;
      if (!(bits > 0)) {
        break;
      }
    }
  }
  return result;
};
 
// Test (256 Bits, 8 Bits per Byte, so 32 Bytes)
var uuid = buildUUID(256);
 
uuid.should.have.a.length.of(32)