(Program
  (Call
    (Identifier)
  {-(Identifier)-}
    (Identifier)
    (Empty))
{+(Context
  {+(Comment)+}
  {+(Call
    {+(Identifier)+}
    {+(Identifier)+}
    {+(Identifier)+}
    {+(Empty)+})+})+}
{-(Call
  {-(Identifier)-}
  {-(Identifier)-}
  {-(Empty)-})-}
{-(Context
  {-(Comment)-}
  {-(Empty)-})-})