SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 6)
    Function CAST (alias t) (children 1)
     ExpressionList (children 2)
      Literal Tuple_(UInt64_1, \'Hello\')
      Literal \'Tuple(x UInt64, s String)\'
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier t
    Function tupleElement (children 1)
     ExpressionList (children 2)
      Identifier t
      Literal UInt64_1
    Function tupleElement (children 1)
     ExpressionList (children 2)
      Identifier t
      Literal UInt64_2
    Function tupleElement (children 1)
     ExpressionList (children 2)
      Identifier t
      Literal \'x\'
    Function tupleElement (children 1)
     ExpressionList (children 2)
      Identifier t
      Literal \'s\'