JS 에서 guid 생성

http://stackoverflow.com/questions/105034/create-guid-uuid-in-javascript 참고함.

'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);
});

//난수 생성을 좀 더 강화하기 위해 Math.random()을 대체한 방법.
var invwk = (function() {
  var max = Math.pow(2, 32),
      seed;
  return {
    setSeed : function(val) {
      seed = val || Math.round(Math.random() * max);
    },
    getSeed : function() {
      return seed;
    },
    rand : function() {
      seed += (seed * seed) | 5;
      return (seed >>> 32) / max;
    }
  };
}());

invwk.setSeed(Date.now());
'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
    var r = invwk.rand()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
    return v.toString(16);
});