diff options
Diffstat (limited to 'antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/LexerIndexedCustomAction.h')
| -rw-r--r-- | antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/LexerIndexedCustomAction.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/LexerIndexedCustomAction.h b/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/LexerIndexedCustomAction.h new file mode 100644 index 0000000..bb371f8 --- /dev/null +++ b/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/LexerIndexedCustomAction.h @@ -0,0 +1,82 @@ +/* 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 "RuleContext.h" +#include "atn/LexerAction.h" + +namespace antlr4 { +namespace atn { + + /// <summary> + /// This implementation of <seealso cref="LexerAction"/> is used for tracking input offsets + /// for position-dependent actions within a <seealso cref="LexerActionExecutor"/>. + /// + /// <para>This action is not serialized as part of the ATN, and is only required for + /// position-dependent lexer actions which appear at a location other than the + /// end of a rule. For more information about DFA optimizations employed for + /// lexer actions, see <seealso cref="LexerActionExecutor#append"/> and + /// <seealso cref="LexerActionExecutor#fixOffsetBeforeMatch"/>.</para> + /// + /// @author Sam Harwell + /// @since 4.2 + /// </summary> + class ANTLR4CPP_PUBLIC LexerIndexedCustomAction final : public LexerAction { + public: + /// <summary> + /// Constructs a new indexed custom action by associating a character offset + /// with a <seealso cref="LexerAction"/>. + /// + /// <para>Note: This class is only required for lexer actions for which + /// <seealso cref="LexerAction#isPositionDependent"/> returns {@code true}.</para> + /// </summary> + /// <param name="offset"> The offset into the input <seealso cref="CharStream"/>, relative to + /// the token start index, at which the specified lexer action should be + /// executed. </param> + /// <param name="action"> The lexer action to execute at a particular offset in the + /// input <seealso cref="CharStream"/>. </param> + LexerIndexedCustomAction(int offset, Ref<LexerAction> const& action); + + /// <summary> + /// Gets the location in the input <seealso cref="CharStream"/> at which the lexer + /// action should be executed. The value is interpreted as an offset relative + /// to the token start index. + /// </summary> + /// <returns> The location in the input <seealso cref="CharStream"/> at which the lexer + /// action should be executed. </returns> + int getOffset() const; + + /// <summary> + /// Gets the lexer action to execute. + /// </summary> + /// <returns> A <seealso cref="LexerAction"/> object which executes the lexer action. </returns> + Ref<LexerAction> getAction() const; + + /// <summary> + /// {@inheritDoc} + /// </summary> + /// <returns> This method returns the result of calling <seealso cref="#getActionType"/> + /// on the <seealso cref="LexerAction"/> returned by <seealso cref="#getAction"/>. </returns> + virtual LexerActionType getActionType() const override; + + /// <summary> + /// {@inheritDoc} </summary> + /// <returns> This method returns {@code true}. </returns> + virtual bool isPositionDependent() const override; + + 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 int _offset; + const Ref<LexerAction> _action; + }; + +} // namespace atn +} // namespace antlr4 + |
