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
20namespace antlr {
21#endif
22
23class ANTLR_API TreeParser {
24public:
25	TreeParser()
26	: astFactory(0)
27	, inputState(new TreeParserInputState())
28	, traceDepth(0)
29	{
30	}
31
32	TreeParser(const TreeParserSharedInputState& state)
33	: astFactory(0)
34	, inputState(state)
35	, traceDepth(0)
36	{
37	}
38
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	 */
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	 */
63	virtual void setASTFactory(ASTFactory* factory)
64	{
65		astFactory = factory;
66	}
67	/// Return pointer to ASTFactory
68	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
98protected:
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
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:
131		Tracer(TreeParser* p, const char* t, RefAST a)
132		: parser(p), text(t), tree(a)
133		{
134			parser->traceIn(text,tree);
135		}
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
145private:
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