SelectWithUnionQuery (children 2)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function extractAllGroupsHorizontal (children 1)
     ExpressionList (children 2)
      Literal \'hello world\'
      Literal \'(\\\\w+)\'
   Set
 Identifier Null
