1 #ifndef INC_TreeParser_hpp__
2 #define INC_TreeParser_hpp__
3 
4 /* ANTLR Translator Generator
5  * Project led by Terence Parr at http://www.jGuru.com
6  * Software rights: http://www.antlr.org/license.html
7  *
8  * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/antlr/TreeParser.hpp#2 $
9  */
10 
11 #include <antlr/config.hpp>
12 #include <antlr/AST.hpp>
13 #include <antlr/ASTFactory.hpp>
14 #include <antlr/BitSet.hpp>
15 #include <antlr/RecognitionException.hpp>
16 #include <antlr/MismatchedTokenException.hpp>
17 #include <antlr/TreeParserSharedInputState.hpp>
18 
19 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
20 namespace antlr {
21 #endif
22 
23 class ANTLR_API TreeParser {
24 public:
TreeParser()25 	TreeParser()
26 	: astFactory(0)
27 	, inputState(new TreeParserInputState())
28 	, traceDepth(0)
29 	{
30 	}
31 
TreeParser(const TreeParserSharedInputState & state)32 	TreeParser(const TreeParserSharedInputState& state)
33 	: astFactory(0)
34 	, inputState(state)
35 	, traceDepth(0)
36 	{
37 	}
38 
~TreeParser()39 	virtual ~TreeParser()
40 	{
41 	}
42 
43 	/// Get the AST return value squirreled away in the parser
44 	virtual RefAST getAST() = 0;
45 
46 	/** Make sure current lookahead symbol matches the given set
47 	 * Throw an exception upon mismatch, which is caught by either the
48 	 * error handler or by a syntactic predicate.
49 	 */
match(RefAST t,const BitSet & b)50 	virtual void match(RefAST t, const BitSet& b)
51 	{
52 		if ( !t || t==ASTNULL || !b.member(t->getType()) )
53 			throw MismatchedTokenException( getTokenNames(), getNumTokens(),
54 													  t, b, false );
55 	}
56 
57 	/** Specify the AST factory to be used during tree building. (Compulsory)
58 	 * Setting the factory is compulsory (if you intend to modify
59 	 * the tree in the treeparser). The AST Factory is shared between
60 	 * parser (who builds the initial AST) and treeparser.
61 	 * @see Parser::getASTFactory()
62 	 */
setASTFactory(ASTFactory * factory)63 	virtual void setASTFactory(ASTFactory* factory)
64 	{
65 		astFactory = factory;
66 	}
67 	/// Return pointer to ASTFactory
getASTFactory() const68 	virtual ASTFactory* getASTFactory() const
69 	{
70 		return astFactory;
71 	}
72 	/// Get the name for token 'num'
73 	virtual const char* getTokenName(int num) const = 0;
74 	/// Return the number of tokens defined
75 	virtual int getNumTokens() const = 0;
76 	/// Return an array of getNumTokens() token names
77 	virtual const char* const* getTokenNames() const = 0;
78 
79 	/// Parser error-reporting function can be overridden in subclass
80 	virtual void reportError(const RecognitionException& ex);
81 	/// Parser error-reporting function can be overridden in subclass
82 	virtual void reportError(const ANTLR_USE_NAMESPACE(std)string& s);
83 	/// Parser warning-reporting function can be overridden in subclass
84 	virtual void reportWarning(const ANTLR_USE_NAMESPACE(std)string& s);
85 
86 	/// These are used during when traceTreeParser commandline option is passed.
87 	virtual void traceIndent();
88 	virtual void traceIn(const char* rname, RefAST t);
89 	virtual void traceOut(const char* rname, RefAST t);
90 
91 	/** The AST Null object; the parsing cursor is set to this when
92 	 * it is found to be null.  This way, we can test the
93 	 * token type of a node without having to have tests for 0
94 	 * everywhere.
95 	 */
96 	static RefAST ASTNULL;
97 
98 protected:
match(RefAST t,int ttype)99 	virtual void match(RefAST t, int ttype)
100 	{
101 		if (!t || t == ASTNULL || t->getType() != ttype )
102 			throw MismatchedTokenException( getTokenNames(), getNumTokens(),
103 													  t, ttype, false );
104 	}
105 
matchNot(RefAST t,int ttype)106 	virtual void matchNot(RefAST t, int ttype)
107 	{
108 		if ( !t || t == ASTNULL || t->getType() == ttype )
109 			throw MismatchedTokenException( getTokenNames(), getNumTokens(),
110 													  t, ttype, true );
111 	}
112 
113 	/** AST support code; parser and treeparser delegate to this object */
114 	ASTFactory* astFactory;
115 
116 	/// The input state of this tree parser.
117 	TreeParserSharedInputState inputState;
118 
119 	/** Used to keep track of indent depth with -traceTreeParser */
120 	int traceDepth;
121 
122 	/** Utility class which allows tracing to work even when exceptions are
123 	 * thrown.
124 	 */
125 	class Tracer {
126 	private:
127 		TreeParser* parser;
128 		const char* text;
129 		RefAST tree;
130 	public:
Tracer(TreeParser * p,const char * t,RefAST a)131 		Tracer(TreeParser* p, const char* t, RefAST a)
132 		: parser(p), text(t), tree(a)
133 		{
134 			parser->traceIn(text,tree);
135 		}
~Tracer()136 		~Tracer()
137 		{
138 			parser->traceOut(text,tree);
139 		}
140 	private:
141 		Tracer(const Tracer&);							// undefined
142 		const Tracer& operator=(const Tracer&);	// undefined
143 	};
144 
145 private:
146 	// no copying of treeparser instantiations...
147 	TreeParser(const TreeParser& other);
148 	TreeParser& operator=(const TreeParser& other);
149 };
150 
151 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
152 }
153 #endif
154 
155 #endif //INC_TreeParser_hpp__
156