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#ifndef INC_Parser_hpp__ |
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#define INC_Parser_hpp__ |
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|
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/* ANTLR Translator Generator |
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* Project led by Terence Parr at http://www.jGuru.com |
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* Software rights: http://www.antlr.org/license.html |
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* |
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* $Id$ |
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*/ |
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|
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#include <iostream> |
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#include <exception> |
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|
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#include <antlr/config.hpp> |
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#include <antlr/BitSet.hpp> |
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#include <antlr/TokenBuffer.hpp> |
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#include <antlr/RecognitionException.hpp> |
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#include <antlr/MismatchedTokenException.hpp> |
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#include <antlr/ASTFactory.hpp> |
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#include <antlr/ParserSharedInputState.hpp> |
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|
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#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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namespace antlr { |
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#endif |
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|
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extern bool DEBUG_PARSER; |
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|
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/** A generic ANTLR parser (LL(k) for k>=1) containing a bunch of |
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* utility routines useful at any lookahead depth. We distinguish between |
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* the LL(1) and LL(k) parsers because of efficiency. This may not be |
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* necessary in the near future. |
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* |
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* Each parser object contains the state of the parse including a lookahead |
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* cache (the form of which is determined by the subclass), whether or |
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* not the parser is in guess mode, where tokens come from, etc... |
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* |
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* <p> |
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* During <b>guess</b> mode, the current lookahead token(s) and token type(s) |
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* cache must be saved because the token stream may not have been informed |
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* to save the token (via <tt>mark</tt>) before the <tt>try</tt> block. |
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* Guessing is started by: |
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* <ol> |
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* <li>saving the lookahead cache. |
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* <li>marking the current position in the TokenBuffer. |
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* <li>increasing the guessing level. |
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* </ol> |
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* |
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* After guessing, the parser state is restored by: |
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* <ol> |
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* <li>restoring the lookahead cache. |
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* <li>rewinding the TokenBuffer. |
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* <li>decreasing the guessing level. |
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* </ol> |
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* |
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* @see antlr.Token |
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* @see antlr.TokenBuffer |
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* @see antlr.TokenStream |
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* @see antlr.LL1Parser |
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* @see antlr.LLkParser |
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* |
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* @todo add constructors with ASTFactory. |
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*/ |
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class ANTLR_API Parser { |
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protected: |
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Parser(TokenBuffer& input) |
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: inputState(new ParserInputState(input)), astFactory(0), traceDepth(0) |
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{ |
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} |
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Parser(TokenBuffer* input) |
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: inputState(new ParserInputState(input)), astFactory(0), traceDepth(0) |
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{ |
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} |
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Parser(const ParserSharedInputState& state) |
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: inputState(state), astFactory(0), traceDepth(0) |
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{ |
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} |
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public: |
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virtual ~Parser() |
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{ |
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} |
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|
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/** Return the token type of the ith token of lookahead where i=1 |
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* is the current token being examined by the parser (i.e., it |
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* has not been matched yet). |
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*/ |
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virtual int LA(unsigned int i)=0; |
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|
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/// Return the i-th token of lookahead |
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virtual RefToken LT(unsigned int i)=0; |
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|
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/** DEPRECATED! Specify the factory to be used during tree building. (Compulsory) |
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* Setting the factory is nowadays compulsory. |
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* @see setASTFactory |
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*/ |
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virtual void setASTNodeFactory( ASTFactory *factory ) |
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{ |
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astFactory = factory; |
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} |
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/** Specify the factory to be used during tree building. (Compulsory) |
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* Setting the factory is nowadays compulsory. |
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*/ |
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virtual void setASTFactory( ASTFactory *factory ) |
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{ |
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astFactory = factory; |
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} |
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/** Return a pointer to the ASTFactory used. |
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* So you might use it in subsequent treewalkers or to reload AST's |
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* from disk. |
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*/ |
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virtual ASTFactory* getASTFactory() |
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{ |
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return astFactory; |
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} |
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/** Get the root AST node of the generated AST. When using a custom AST type |
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* or heterogenous AST's, you'll have to convert it to the right type |
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* yourself. |
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*/ |
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virtual RefAST getAST() = 0; |
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|
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/// Return the filename of the input file. |
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virtual inline ANTLR_USE_NAMESPACE(std)string getFilename() const |
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{ |
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return inputState->filename; |
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} |
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/// Set the filename of the input file (used for error reporting). |
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virtual void setFilename(const ANTLR_USE_NAMESPACE(std)string& f) |
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{ |
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inputState->filename = f; |
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} |
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|
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virtual void setInputState(ParserSharedInputState state) |
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{ |
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inputState = state; |
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} |
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virtual inline ParserSharedInputState getInputState() const |
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{ |
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return inputState; |
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} |
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|
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/// Get another token object from the token stream |
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virtual void consume()=0; |
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/// Consume tokens until one matches the given token |
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virtual void consumeUntil(int tokenType) |
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{ |
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while (LA(1) != Token::EOF_TYPE && LA(1) != tokenType) |
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consume(); |
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} |
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|
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/// Consume tokens until one matches the given token set |
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virtual void consumeUntil(const BitSet& set) |
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{ |
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while (LA(1) != Token::EOF_TYPE && !set.member(LA(1))) |
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consume(); |
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} |
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|
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/** Make sure current lookahead symbol matches token type <tt>t</tt>. |
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* Throw an exception upon mismatch, which is catch by either the |
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* error handler or by the syntactic predicate. |
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*/ |
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virtual void match(int t) |
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{ |
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if ( DEBUG_PARSER ) |
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{ |
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traceIndent(); |
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ANTLR_USE_NAMESPACE(std)cout << "enter match(" << t << ") with LA(1)=" << LA(1) << ANTLR_USE_NAMESPACE(std)endl; |
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} |
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if ( LA(1) != t ) |
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{ |
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if ( DEBUG_PARSER ) |
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{ |
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traceIndent(); |
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ANTLR_USE_NAMESPACE(std)cout << "token mismatch: " << LA(1) << "!=" << t << ANTLR_USE_NAMESPACE(std)endl; |
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} |
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throw MismatchedTokenException(getTokenNames(), getNumTokens(), LT(1), t, false, getFilename()); |
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} |
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else |
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{ |
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// mark token as consumed -- fetch next token deferred until LA/LT |
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consume(); |
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} |
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} |
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|
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virtual void matchNot(int t) |
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{ |
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if ( LA(1)==t ) |
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{ |
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// Throws inverted-sense exception |
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throw MismatchedTokenException(getTokenNames(), getNumTokens(), LT(1), t, true, getFilename()); |
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} |
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else |
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{ |
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// mark token as consumed -- fetch next token deferred until LA/LT |
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consume(); |
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} |
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} |
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|
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/** Make sure current lookahead symbol matches the given set |
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* Throw an exception upon mismatch, which is catch by either the |
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* error handler or by the syntactic predicate. |
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*/ |
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virtual void match(const BitSet& b) |
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{ |
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if ( DEBUG_PARSER ) |
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{ |
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traceIndent(); |
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ANTLR_USE_NAMESPACE(std)cout << "enter match(" << "bitset" /*b.toString()*/ |
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<< ") with LA(1)=" << LA(1) << ANTLR_USE_NAMESPACE(std)endl; |
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} |
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if ( !b.member(LA(1)) ) |
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{ |
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if ( DEBUG_PARSER ) |
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{ |
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traceIndent(); |
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ANTLR_USE_NAMESPACE(std)cout << "token mismatch: " << LA(1) << " not member of " |
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<< "bitset" /*b.toString()*/ << ANTLR_USE_NAMESPACE(std)endl; |
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} |
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throw MismatchedTokenException(getTokenNames(), getNumTokens(), LT(1), b, false, getFilename()); |
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} |
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else |
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{ |
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// mark token as consumed -- fetch next token deferred until LA/LT |
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consume(); |
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} |
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} |
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|
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/** Mark a spot in the input and return the position. |
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* Forwarded to TokenBuffer. |
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*/ |
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virtual inline unsigned int mark() |
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{ |
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return inputState->getInput().mark(); |
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} |
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/// rewind to a previously marked position |
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virtual inline void rewind(unsigned int pos) |
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{ |
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inputState->getInput().rewind(pos); |
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} |
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/** called by the generated parser to do error recovery, override to |
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* customize the behaviour. |
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*/ |
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virtual void recover(const RecognitionException& ex, const BitSet& tokenSet) |
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{ |
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consume(); |
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consumeUntil(tokenSet); |
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} |
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|
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/// Parser error-reporting function can be overridden in subclass |
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virtual void reportError(const RecognitionException& ex); |
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/// Parser error-reporting function can be overridden in subclass |
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virtual void reportError(const ANTLR_USE_NAMESPACE(std)string& s); |
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/// Parser warning-reporting function can be overridden in subclass |
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virtual void reportWarning(const ANTLR_USE_NAMESPACE(std)string& s); |
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|
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/// get the token name for the token number 'num' |
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virtual const char* getTokenName(int num) const = 0; |
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/// get a vector with all token names |
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virtual const char* const* getTokenNames() const = 0; |
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/** Get the number of tokens defined. |
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* This one should be overridden in subclasses. |
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*/ |
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virtual int getNumTokens(void) const = 0; |
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|
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/** Set or change the input token buffer */ |
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// void setTokenBuffer(TokenBuffer<Token>* t); |
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|
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virtual void traceIndent(); |
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virtual void traceIn(const char* rname); |
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virtual void traceOut(const char* rname); |
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protected: |
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// void setTokenNames(const char** tokenNames_); |
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|
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ParserSharedInputState inputState; |
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|
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// /// AST return value for a rule is squirreled away here |
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// RefAST returnAST; |
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|
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/// AST support code; parser and treeparser delegate to this object |
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ASTFactory *astFactory; |
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|
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// used to keep track of the indentation for the trace |
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int traceDepth; |
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|
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/** Utility class which allows tracing to work even when exceptions are |
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* thrown. |
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*/ |
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class Tracer { /*{{{*/ |
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private: |
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Parser* parser; |
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const char* text; |
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public: |
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Tracer(Parser* p,const char * t) |
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: parser(p), text(t) |
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{ |
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parser->traceIn(text); |
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} |
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~Tracer() |
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{ |
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#ifdef ANTLR_CXX_SUPPORTS_UNCAUGHT_EXCEPTION |
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// Only give trace if there's no uncaught exception.. |
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if(!ANTLR_USE_NAMESPACE(std)uncaught_exception()) |
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#endif |
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parser->traceOut(text); |
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} |
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private: |
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Tracer(const Tracer&); // undefined |
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const Tracer& operator=(const Tracer&); // undefined |
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/*}}}*/ |
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}; |
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private: |
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Parser(const Parser&); // undefined |
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const Parser& operator=(const Parser&); // undefined |
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}; |
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|
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#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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} |
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#endif |
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|
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#endif //INC_Parser_hpp__ |