(Program
  (Call
    (Identifier)
  {+(Identifier)+}
    (Empty))
  (Call
    (Identifier)
  {-(Identifier)-}
    (Empty))
  (Call
    (Identifier)
  {-(Identifier)-}
    (Identifier)
  {+(Identifier)+}
    (Empty))
{-(Call
  {-(MemberAccess
    {-(Identifier)-}
    {-(Identifier)-})-}
  {-(Integer)-}
  {-(Empty)-})-})