=========================
Simple Declaration
=========================
parser simple() {
  state start {
    bool l;
    transition accept;
  }
};

---
(p4program
 (declaration
  (parserDeclaration
   (parserType
    (parser)
    (identifier)
   )
   (parserStates
    (parserState
     (state)
     (identifier)
     (parserLocalElements
      (parserLocalElement
       (variableDeclaration
        (typeRef
         (baseType
          (bool)
         )
        )
        (identifier)
       )
      )
      (semicolon)
     )
     (parserTransitionStatement
      (transition)
      (transitionSelectionExpression
       (identifier)
      )
     )
     (semicolon)
    )
   )
  )
  (semicolon)
 )
)