(Program
  (Object
    (Pair
    { (Identifier)
    ->(SymbolLiteral) }
    { (StringLiteral)
    ->(StringLiteral) })
    (Pair
    { (Identifier)
    ->(SymbolLiteral) }
    { (IntegerLiteral)
    ->(IntegerLiteral) })
    (Pair
    { (Identifier)
    ->(StringLiteral) }
    { (Boolean)
    ->(Boolean) })
  {+(Pair
      (SymbolLiteral)
      (IntegerLiteral))+})
{+(Object)+}
{+(Object
    (Comment)
    (Pair
      (Identifier)
      (IntegerLiteral))
    (Comment)
    (Comment)
    (Pair
      (StringLiteral)
      (IntegerLiteral))
    (Comment))+}
{+(Object
    (Comment))+})