src/antlr/TokenStreamHiddenTokenFilter.hpp

#ifndef INC_TokenStreamHiddenTokenFilter_hpp__
#define INC_TokenStreamHiddenTokenFilter_hpp__

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/license.html
 *
 * $Id: TokenStreamHiddenTokenFilter.hpp,v 1.1 2005-12-02 15:38:02 tim Exp $
 */

#include <antlr/config.hpp>
#include <antlr/TokenStreamBasicFilter.hpp>

#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
namespace antlr {
#endif

/**This object filters a token stream coming from a lexer
 * or another TokenStream so that only certain token channels
 * get transmitted to the parser.
 *
 * Any of the channels can be filtered off as "hidden" channels whose
 * tokens can be accessed from the parser.
 */
class ANTLR_API TokenStreamHiddenTokenFilter : public TokenStreamBasicFilter {
        // protected BitSet discardMask;
protected:
        BitSet hideMask;

private:
        RefToken nextMonitoredToken;

protected:
        /** track tail of hidden list emanating from previous
         *  monitored token
         */
        RefToken lastHiddenToken;

        RefToken firstHidden; // = null;

public:
        TokenStreamHiddenTokenFilter(TokenStream& input);

protected:
        void consume();

private:
        void consumeFirst();

public:
        BitSet getDiscardMask() const;

        /** Return a ptr to the hidden token appearing immediately after
         *  token t in the input stream.
         */
        RefToken getHiddenAfter(RefToken t);

        /** Return a ptr to the hidden token appearing immediately before
         *  token t in the input stream.
         */
        RefToken getHiddenBefore(RefToken t);

        BitSet getHideMask() const;

        /** Return the first hidden token if one appears
         *  before any monitored token.
         */
        RefToken getInitialHiddenToken();

        void hide(int m);

        void hide(const BitSet& mask);

protected:
        RefToken LA(int i);

public:
/** Return the next monitored token.
 *  Test the token following the monitored token.
 *  If following is another monitored token, save it
 *  for the next invocation of nextToken (like a single
 *  lookahead token) and return it then.
 *  If following is unmonitored, nondiscarded (hidden)
 *  channel token, add it to the monitored token.
 *
 *  Note: EOF must be a monitored Token.
 */
        RefToken nextToken();
};

#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
}
#endif

#endif //INC_TokenStreamHiddenTokenFilter_hpp__
Revision:	2469
Committed:	Fri Dec 2 15:38:03 2005 UTC (18 years, 7 months ago) by tim
File size:	2277 byte(s)
Log Message:	End of the Link --> List Return of the Oject-Oriented replace yacc/lex parser with antlr parser
#	Content
1	#ifndef INC_TokenStreamHiddenTokenFilter_hpp__
2	#define INC_TokenStreamHiddenTokenFilter_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: TokenStreamHiddenTokenFilter.hpp,v 1.1 2005-12-02 15:38:02 tim Exp $
9	*/
10
11	#include <antlr/config.hpp>
12	#include <antlr/TokenStreamBasicFilter.hpp>
13
14	#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
15	namespace antlr {
16	#endif
17
18	/**This object filters a token stream coming from a lexer
19	* or another TokenStream so that only certain token channels
20	* get transmitted to the parser.
21	*
22	* Any of the channels can be filtered off as "hidden" channels whose
23	* tokens can be accessed from the parser.
24	*/
25	class ANTLR_API TokenStreamHiddenTokenFilter : public TokenStreamBasicFilter {
26	// protected BitSet discardMask;
27	protected:
28	BitSet hideMask;
29
30	private:
31	RefToken nextMonitoredToken;
32
33	protected:
34	/** track tail of hidden list emanating from previous
35	* monitored token
36	*/
37	RefToken lastHiddenToken;
38
39	RefToken firstHidden; // = null;
40
41	public:
42	TokenStreamHiddenTokenFilter(TokenStream& input);
43
44	protected:
45	void consume();
46
47	private:
48	void consumeFirst();
49
50	public:
51	BitSet getDiscardMask() const;
52
53	/** Return a ptr to the hidden token appearing immediately after
54	* token t in the input stream.
55	*/
56	RefToken getHiddenAfter(RefToken t);
57
58	/** Return a ptr to the hidden token appearing immediately before
59	* token t in the input stream.
60	*/
61	RefToken getHiddenBefore(RefToken t);
62
63	BitSet getHideMask() const;
64
65	/** Return the first hidden token if one appears
66	* before any monitored token.
67	*/
68	RefToken getInitialHiddenToken();
69
70	void hide(int m);
71
72	void hide(const BitSet& mask);
73
74	protected:
75	RefToken LA(int i);
76
77	public:
78	/** Return the next monitored token.
79	* Test the token following the monitored token.
80	* If following is another monitored token, save it
81	* for the next invocation of nextToken (like a single
82	* lookahead token) and return it then.
83	* If following is unmonitored, nondiscarded (hidden)
84	* channel token, add it to the monitored token.
85	*
86	* Note: EOF must be a monitored Token.
87	*/
88	RefToken nextToken();
89	};
90
91	#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
92	}
93	#endif
94
95	#endif //INC_TokenStreamHiddenTokenFilter_hpp__