public String toEscapedString(){
  StringBuilder sb=new StringBuilder();
  toStringBuilderEscaped(sb);
  return sb.toString();
}

public String toEscapedString ( ) { StringBuilder sb = new StringBuilder ( ) ; toStringBuilderEscaped ( sb ) ; return sb . toString ( ) ; }
same as tostring ( ) , but escapes terminals like so : ( becomes - lrb - ) becomes - rrb - \ becomes - backslash - ( " \ " does not occur in ptb ; this is our own convention ) this is useful because otherwise it ' s hard to tell a " ( " terminal from the tree ' s bracket structure , or tell an escaping \ from a literal .
