code: function(doc){
  	var vs=doc.split("\r\n");
  	if(vs.length==1){
  		vs=doc.split("\n");
  	}
  	if(vs[vs.length-1]==''){
  		vs.pop();
  	}
  	return vs;
  }
docs: split string by line terminator
  @param doc   target document
  @return      splited document