var SingletonClass={create:function singletonclass__create()
{var ProtoClass=Class.create.apply(Class,arguments);var instance;ProtoClass=Class.create(ProtoClass,{initialize:function($super)
{if(instance)
throw("cannot create another - this is a singleton");$super();}});instance=new ProtoClass();ProtoClass.get=function(){return instance;};return ProtoClass;}};