void function() {//abcd
  

  do break;while(typeof delete this);
  

  for(var a;;)
  

  if (true)  with(null)
  

  try{}catch(a){}finally{} else throw new 1;
  

  

  switch(1 in 1 instanceof 1) {
  

  case false:
  

  default:
  

  }
  

  return;
  

  };
 

  new function() {
  

  do break;while(typeof delete this);
  

  for(var a;void 0;)
  

  continue
  

  if (null)
  

  with(0)
  

  try{
  

  switch(1 in 1 instanceof 1) {
  

  case false:
  

  default:throw true
  

  }
  

  }catch(a){}finally{}else return  // console.log("去掉注释可以运行到这里")
  

  };