/* 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>
/// Implements the {@code skip} lexer action by calling <seealso cref="Lexer#skip"/>.
///
/// <para>The {@code skip} command does not have any parameters, so this action is
/// implemented as a singleton instance exposed by <seealso cref="#INSTANCE"/>.</para>
///
/// @author Sam Harwell
/// @since 4.2
/// </summary>
class ANTLR4CPP_PUBLIC LexerSkipAction final : public LexerAction {
public:
    /// Provides a singleton instance of this parameterless lexer action.
    static const Ref<LexerSkipAction> getInstance();

    /// <summary>
    /// {@inheritDoc} </summary>
    /// <returns> This method returns <seealso cref="LexerActionType#SKIP"/>. </returns>
    virtual LexerActionType getActionType() const override;

    /// <summary>
    /// {@inheritDoc} </summary>
    /// <returns> This method returns {@code false}. </returns>
    virtual bool isPositionDependent() const override;

    /// <summary>
    /// {@inheritDoc}
    ///
    /// <para>This action is implemented by calling <seealso cref="Lexer#skip"/>.</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:
    /// Constructs the singleton instance of the lexer {@code skip} command.
    LexerSkipAction();
};

} // namespace atn
} // namespace antlr4
