=========================
Simple Control Declaration
=========================
control simple() {
  action a() {
  }
  table t {
    key = {
      x: exact;
    }
  }
  apply {
  }
};

---
(p4program
 (declaration
  (control_declaration
   (control)
   (identifier)
   (parameters)
   (action_declaration
    (action)
    (identifier)
    (parameters)
    (statement
     (blockStatement)
    )
   )
   (table_declaration
    (table)
    (identifier)
    (table_property_list
     (table_keys
      (key)
      (table_key_entry
       (keysetExpression
        (expression
         (simple_expression
          (identifier)
         )
        )
       )
       (table_key_match_type
        (exact) 
       )
      )  
     )
    )
   )
   (apply)
   (statement
    (blockStatement)
   )
  )
 )
)