Parser.cpp
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上传日期:2007-01-06
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- /**
- * <b>SOFTWARE RIGHTS</b>
- * <p>
- * ANTLR 2.6.0 MageLang Insitute, 1998
- * <p>
- * We reserve no legal rights to the ANTLR--it is fully in the
- * public domain. An individual or company may do whatever
- * they wish with source code distributed with ANTLR or the
- * code generated by ANTLR, including the incorporation of
- * ANTLR, or its output, into commerical software.
- * <p>
- * We encourage users to develop software with ANTLR. However,
- * we do ask that credit is given to us for developing
- * ANTLR. By "credit", we mean that if you use ANTLR or
- * incorporate any source code into one of your programs
- * (commercial product, research project, or otherwise) that
- * you acknowledge this fact somewhere in the documentation,
- * research report, etc... If you like ANTLR and have
- * developed a nice tool with the output, please mention that
- * you developed it using ANTLR. In addition, we ask that the
- * headers remain intact in our source code. As long as these
- * guidelines are kept, we expect to continue enhancing this
- * system and expect to make other tools available as they are
- * completed.
- * <p>
- * The ANTLR gang:
- * @version ANTLR 2.6.0 MageLang Insitute, 1998
- * @author Terence Parr, <a href=http://www.MageLang.com>MageLang Institute</a>
- * @author <br>John Lilley, <a href=http://www.Empathy.com>Empathy Software</a>
- * @author <br><a href="mailto:pete@yamuna.demon.co.uk">Pete Wells</a>
- */
- #include "antlr/Parser.hpp"
- #include "antlr/BitSet.hpp"
- #include "antlr/TokenBuffer.hpp"
- #include "antlr/MismatchedTokenException.hpp"
- //#include "antlr/ASTFactory.hpp"
- #include <iostream>
- ANTLR_BEGIN_NAMESPACE(antlr)
- /**A generic ANTLR parser (LL(k) for k>=1) containing a bunch of
- * utility routines useful at any lookahead depth. We distinguish between
- * the LL(1) and LL(k) parsers because of efficiency. This may not be
- * necessary in the near future.
- *
- * Each parser object contains the state of the parse including a lookahead
- * cache (the form of which is determined by the subclass), whether or
- * not the parser is in guess mode, where tokens come from, etc...
- *
- * <p>
- * During <b>guess</b> mode, the current lookahead token(s) and token type(s)
- * cache must be saved because the token stream may not have been informed
- * to save the token (via <tt>mark</tt>) before the <tt>try</tt> block.
- * Guessing is started by:
- * <ol>
- * <li>saving the lookahead cache.
- * <li>marking the current position in the TokenBuffer.
- * <li>increasing the guessing level.
- * </ol>
- *
- * After guessing, the parser state is restored by:
- * <ol>
- * <li>restoring the lookahead cache.
- * <li>rewinding the TokenBuffer.
- * <li>decreasing the guessing level.
- * </ol>
- *
- * @see antlr.Token
- * @see antlr.TokenBuffer
- * @see antlr.TokenStream
- * @see antlr.LL1Parser
- * @see antlr.LLkParser
- */
- bool DEBUG_PARSER=false;
- Parser::Parser(TokenBuffer& input)
- : inputState(new ParserInputState(input))
- {
- }
- Parser::Parser(TokenBuffer* input)
- : inputState(new ParserInputState(input))
- {
- }
- Parser::Parser(const ParserSharedInputState& state)
- : inputState(state)
- {
- }
- Parser::~Parser()
- {
- }
- void Parser::setTokenNames(const char** tokenNames_)
- {
- while (*tokenNames_) {
- tokenNames.push_back(*(tokenNames_++));
- }
- }
- /** Consume tokens until one matches the given token */
- void Parser::consumeUntil(int tokenType)
- {
- while (LA(1) != Token::EOF_TYPE && LA(1) != tokenType)
- consume();
- }
- /** Consume tokens until one matches the given token set */
- void Parser::consumeUntil(const BitSet& set)
- {
- while (LA(1) != Token::EOF_TYPE && !set.member(LA(1)))
- consume();
- }
- /** Get the AST return value squirreled away in the parser */
- RefAST Parser::getAST()
- {
- return returnAST;
- }
- ASTFactory& Parser::getASTFactory()
- {
- return astFactory;
- }
- ANTLR_USE_NAMESPACE(std)string Parser::getFilename() const
- {
- return inputState->filename;
- }
- ParserSharedInputState Parser::getInputState() const
- {
- return inputState;
- }
- ANTLR_USE_NAMESPACE(std)string Parser::getTokenName(int num) const
- {
- return tokenNames[num];
- }
- ANTLR_USE_NAMESPACE(std)vector<ANTLR_USE_NAMESPACE(std)string> Parser::getTokenNames() const
- {
- return tokenNames;
- }
- // Forwarded to TokenBuffer
- int Parser::mark()
- {
- return inputState->getInput().mark();
- }
- /**Make sure current lookahead symbol matches token type <tt>t</tt>.
- * Throw an exception upon mismatch, which is catch by either the
- * error handler or by the syntactic predicate.
- */
- void Parser::match(int t)
- {
- if ( DEBUG_PARSER )
- ANTLR_USE_NAMESPACE(std)cout << "enter match(" << t << ") with LA(1)=" << LA(1) << ANTLR_USE_NAMESPACE(std)endl;
- if ( LA(1)!=t ) {
- if ( DEBUG_PARSER )
- ANTLR_USE_NAMESPACE(std)cout << "token mismatch: " << LA(1) << "!=" << t << ANTLR_USE_NAMESPACE(std)endl;
- throw MismatchedTokenException(tokenNames, LT(1), t, false, getFilename());
- } else {
- // mark token as consumed -- fetch next token deferred until LA/LT
- consume();
- }
- }
- /**Make sure current lookahead symbol matches the given set
- * Throw an exception upon mismatch, which is catch by either the
- * error handler or by the syntactic predicate.
- */
- void Parser::match(const BitSet& b)
- {
- if ( DEBUG_PARSER )
- ANTLR_USE_NAMESPACE(std)cout << "enter match(" << "bitset" /*b.toString()*/
- << ") with LA(1)=" << LA(1) << ANTLR_USE_NAMESPACE(std)endl;
- if ( !b.member(LA(1)) ) {
- if ( DEBUG_PARSER )
- ANTLR_USE_NAMESPACE(std)cout << "token mismatch: " << LA(1) << " not member of "
- << "bitset" /*b.toString()*/ << ANTLR_USE_NAMESPACE(std)endl;
- throw MismatchedTokenException(tokenNames, LT(1), b, false, getFilename());
- } else {
- // mark token as consumed -- fetch next token deferred until LA/LT
- consume();
- }
- }
- void Parser::matchNot(int t)
- {
- if ( LA(1)==t ) {
- // Throws inverted-sense exception
- throw MismatchedTokenException(tokenNames, LT(1), t, true, getFilename());
- } else {
- // mark token as consumed -- fetch next token deferred until LA/LT
- consume();
- }
- }
- void Parser::panic()
- {
- ANTLR_USE_NAMESPACE(std)cerr << "Parser: panic" << ANTLR_USE_NAMESPACE(std)endl;
- exit(1);
- }
- /** Parser error-reporting function can be overridden in subclass */
- void Parser::reportError(const RecognitionException& ex)
- {
- ANTLR_USE_NAMESPACE(std)cerr << ex.toString().c_str() << ANTLR_USE_NAMESPACE(std)endl;
- }
- /** Parser error-reporting function can be overridden in subclass */
- void Parser::reportError(const ANTLR_USE_NAMESPACE(std)string& s)
- {
- if ( getFilename()=="" )
- ANTLR_USE_NAMESPACE(std)cerr << "error: " << s.c_str() << ANTLR_USE_NAMESPACE(std)endl;
- else
- ANTLR_USE_NAMESPACE(std)cerr << getFilename().c_str() << ": error: " << s.c_str() << ANTLR_USE_NAMESPACE(std)endl;
- }
- /** Parser warning-reporting function can be overridden in subclass */
- void Parser::reportWarning(const ANTLR_USE_NAMESPACE(std)string& s)
- {
- if ( getFilename()=="" )
- ANTLR_USE_NAMESPACE(std)cerr << "warning: " << s.c_str() << ANTLR_USE_NAMESPACE(std)endl;
- else
- ANTLR_USE_NAMESPACE(std)cerr << getFilename().c_str() << ": warning: " << s.c_str() << ANTLR_USE_NAMESPACE(std)endl;
- }
- void Parser::rewind(int pos)
- {
- inputState->getInput().rewind(pos);
- }
- /** Set the object used to generate ASTs */
- // void setASTFactory(ASTFactory astFactory_);
- /** Specify the type of node to create during tree building */
- void Parser::setASTNodeFactory(ASTFactory::factory_type factory)
- {
- astFactory.setASTNodeFactory(factory);
- }
- void Parser::setFilename(const ANTLR_USE_NAMESPACE(std)string& f)
- {
- inputState->filename = f;
- }
- void Parser::setInputState(ParserSharedInputState state)
- {
- inputState = state;
- }
- /** Set or change the input token buffer */
- // void setTokenBuffer(TokenBuffer<Token>* t);
- void Parser::traceIn(const ANTLR_USE_NAMESPACE(std)string& rname)
- {
- ANTLR_USE_NAMESPACE(std)cout << "enter " << rname.c_str() << "; LA(1)==" << LT(1)->getText().c_str() <<
- ((inputState->guessing>0)?" [guessing]":"") << ANTLR_USE_NAMESPACE(std)endl;
- }
- void Parser::traceOut(const ANTLR_USE_NAMESPACE(std)string& rname)
- {
- ANTLR_USE_NAMESPACE(std)cout << "exit " << rname.c_str() << "; LA(1)==" << LT(1)->getText().c_str() <<
- ((inputState->guessing>0)?" [guessing]":"") << ANTLR_USE_NAMESPACE(std)endl;
- }
- ANTLR_END_NAMESPACE