code: private void parseForExpr() throws TTXPathException {
  
          // get number of all for conditions
          final int rangeVarNo = parseSimpleForClause();
          consume("return", true);
  
          // parse return clause
          parseExprSingle();
  
          mPipeBuilder.addForExpression(rangeVarNo);
  
      }
docs: Parses the the rule ForExpr according to the following production rule:
  [4]
  <p>
  ForExpr ::= SimpleForClause "return" ExprSingle .
  </p>
  
  @throws TTXPathException