(Statements
  (If
    (Send
    { (Identifier)
    ->(Identifier) })
    (Statements
    {-(Send
      {-(Identifier)-})-})
  { (If
    {-(Send
      {-(Identifier)-})-}
    {-(Statements
      {-(Send
        {-(Identifier)-})-})-}
    {-(Send
      {-(Identifier)-})-})
  ->(Empty) })
{+(If
  {+(Send
    {+(Identifier)+})+}
  {+(Statements)+}
  {+(Empty)+})+})