60 lines
2.4 KiB
C
60 lines
2.4 KiB
C
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/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
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* Use of this file is governed by the BSD 3-clause license that
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* can be found in the LICENSE.txt file in the project root.
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*/
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#pragma once
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#include "DefaultErrorStrategy.h"
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namespace antlr4 {
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/**
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* This implementation of {@link ANTLRErrorStrategy} responds to syntax errors
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* by immediately canceling the parse operation with a
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* {@link ParseCancellationException}. The implementation ensures that the
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* {@link ParserRuleContext#exception} field is set for all parse tree nodes
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* that were not completed prior to encountering the error.
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*
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* <p>
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* This error strategy is useful in the following scenarios.</p>
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*
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* <ul>
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* <li><strong>Two-stage parsing:</strong> This error strategy allows the first
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* stage of two-stage parsing to immediately terminate if an error is
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* encountered, and immediately fall back to the second stage. In addition to
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* avoiding wasted work by attempting to recover from errors here, the empty
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* implementation of {@link BailErrorStrategy#sync} improves the performance of
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* the first stage.</li>
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* <li><strong>Silent validation:</strong> When syntax errors are not being
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* reported or logged, and the parse result is simply ignored if errors occur,
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* the {@link BailErrorStrategy} avoids wasting work on recovering from errors
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* when the result will be ignored either way.</li>
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* </ul>
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*
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* <p>
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* {@code myparser.setErrorHandler(new BailErrorStrategy());}</p>
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*
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* @see Parser#setErrorHandler(ANTLRErrorStrategy)
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*/
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class ANTLR4CPP_PUBLIC BailErrorStrategy : public DefaultErrorStrategy {
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/// <summary>
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/// Instead of recovering from exception {@code e}, re-throw it wrapped
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/// in a <seealso cref="ParseCancellationException"/> so it is not caught by the
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/// rule function catches. Use <seealso cref="Exception#getCause()"/> to get the
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/// original <seealso cref="RecognitionException"/>.
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/// </summary>
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public:
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virtual void recover(Parser *recognizer, std::exception_ptr e) override;
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/// Make sure we don't attempt to recover inline; if the parser
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/// successfully recovers, it won't throw an exception.
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virtual Token* recoverInline(Parser *recognizer) override;
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/// <summary>
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/// Make sure we don't attempt to recover from problems in subrules. </summary>
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virtual void sync(Parser *recognizer) override;
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};
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} // namespace antlr4
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