Line data    Source code

       1             : /* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
       2             :  * Use of this file is governed by the BSD 3-clause license that
       3             :  * can be found in the LICENSE.txt file in the project root.
       4             :  */
       5             : 
       6             : #pragma once
       7             : 
       8             : #include "antlr4-common.h"
       9             : 
      10             : namespace antlr4 {
      11             : namespace tree {
      12             : 
      13             :   /** This interface describes the minimal core of methods triggered
      14             :    *  by {@link ParseTreeWalker}. E.g.,
      15             :    *
      16             :    *    ParseTreeWalker walker = new ParseTreeWalker();
      17             :    *            walker.walk(myParseTreeListener, myParseTree); <-- triggers events in your listener
      18             :    *
      19             :    *  If you want to trigger events in multiple listeners during a single
      20             :    *  tree walk, you can use the ParseTreeDispatcher object available at
      21             :    *
      22             :    *            https://github.com/antlr/antlr4/issues/841
      23             :    */
      24           0 :   class ANTLR4CPP_PUBLIC ParseTreeListener {
      25             :   public:
      26             :     virtual ~ParseTreeListener();
      27             : 
      28             :     virtual void visitTerminal(TerminalNode *node) = 0;
      29             :     virtual void visitErrorNode(ErrorNode *node) = 0;
      30             :     virtual void enterEveryRule(ParserRuleContext *ctx) = 0;
      31             :     virtual void exitEveryRule(ParserRuleContext *ctx) = 0;
      32             : 
      33             :     bool operator == (const ParseTreeListener &other) {
      34             :       return this == &other;
      35             :     }
      36             :   };
      37             : 
      38             : } // namespace tree
      39             : } // namespace antlr4