--- /dev/null
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#pragma once
+
+#include "atn/LexerAction.h"
+#include "atn/LexerActionType.h"
+
+namespace antlr4 {
+namespace atn {
+
+ /// <summary>
+ /// Executes a custom lexer action by calling <seealso cref="Recognizer#action"/> with the
+ /// rule and action indexes assigned to the custom action. The implementation of
+ /// a custom action is added to the generated code for the lexer in an override
+ /// of <seealso cref="Recognizer#action"/> when the grammar is compiled.
+ ///
+ /// <para>This class may represent embedded actions created with the <code>{...}</code>
+ /// syntax in ANTLR 4, as well as actions created for lexer commands where the
+ /// command argument could not be evaluated when the grammar was compiled.</para>
+ ///
+ /// @author Sam Harwell
+ /// @since 4.2
+ /// </summary>
+ class ANTLR4CPP_PUBLIC LexerCustomAction final : public LexerAction {
+ public:
+ /// <summary>
+ /// Constructs a custom lexer action with the specified rule and action
+ /// indexes.
+ /// </summary>
+ /// <param name="ruleIndex"> The rule index to use for calls to
+ /// <seealso cref="Recognizer#action"/>. </param>
+ /// <param name="actionIndex"> The action index to use for calls to
+ /// <seealso cref="Recognizer#action"/>. </param>
+ LexerCustomAction(size_t ruleIndex, size_t actionIndex);
+
+ /// <summary>
+ /// Gets the rule index to use for calls to <seealso cref="Recognizer#action"/>.
+ /// </summary>
+ /// <returns> The rule index for the custom action. </returns>
+ size_t getRuleIndex() const;
+
+ /// <summary>
+ /// Gets the action index to use for calls to <seealso cref="Recognizer#action"/>.
+ /// </summary>
+ /// <returns> The action index for the custom action. </returns>
+ size_t getActionIndex() const;
+
+ /// <summary>
+ /// {@inheritDoc}
+ /// </summary>
+ /// <returns> This method returns <seealso cref="LexerActionType#CUSTOM"/>. </returns>
+ virtual LexerActionType getActionType() const override;
+
+ /// <summary>
+ /// Gets whether the lexer action is position-dependent. Position-dependent
+ /// actions may have different semantics depending on the <seealso cref="CharStream"/>
+ /// index at the time the action is executed.
+ ///
+ /// <para>Custom actions are position-dependent since they may represent a
+ /// user-defined embedded action which makes calls to methods like
+ /// <seealso cref="Lexer#getText"/>.</para>
+ /// </summary>
+ /// <returns> This method returns {@code true}. </returns>
+ virtual bool isPositionDependent() const override;
+
+ /// <summary>
+ /// {@inheritDoc}
+ ///
+ /// <para>Custom actions are implemented by calling <seealso cref="Lexer#action"/> with the
+ /// appropriate rule and action indexes.</para>
+ /// </summary>
+ virtual void execute(Lexer *lexer) override;
+
+ virtual size_t hashCode() const override;
+ virtual bool operator == (const LexerAction &obj) const override;
+ virtual std::string toString() const override;
+
+ private:
+ const size_t _ruleIndex;
+ const size_t _actionIndex;
+ };
+
+} // namespace atn
+} // namespace antlr4