summaryrefslogtreecommitdiffstats
path: root/kalzium/src/parser.h
blob: 84007a7c2973ffaa5d76441a6b41b3c3552bc33d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
/***************************************************************************
    copyright            : (C) 2005 by Inge Wallin
    email                : [email protected]
 ***************************************************************************/
/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef PARSER_H
#define PARSER_H

#include <tqstring.h>

/**
 * This is a general purpose parser originally written by Inge Wallin.
 *
 * It is intended to be subclassed; see MoleculeParser.
 *
 * @author Inge Wallin
 */
class Parser {
public:
    // All characters are their own token value per default.
    static const  int  INT_TOKEN   = 257;
    static const  int  FLOAT_TOKEN = 258;
    // Extend this list in your subclass to make a more advanced parser.

    Parser();
    Parser(const TQString& _str);
    ~Parser();

    /**
     * Start a new parse.
     */
    void   start(const TQString& _str);

    /**
     * Peek at the next character;
     */
    int    nextChar()  const { return m_nextChar;  }

    /**
     * Peek at the next token.
     */
    int    nextToken() const { return m_nextToken; }

    /**
     * Get the value stored for different types of tokens.
     */
    int    intVal()    const { return m_intVal;    }
    float  floatVal()  const { return m_floatVal;  }

private:

    // Try to parse some special datatypes.
    bool  parseInt(int *_result);
    bool  parseSimpleFloat(double *_result);

protected:

    /**
     * Make the next character the current one.
     */
    int   getNextChar();

    /**
     * Make the next non-space character the current one.
     */
    int   skipWhitespace();

    /**
     * Fetches the next token.
     */
    virtual int   getNextToken();

private:
    TQString  m_str;
    int      m_index;
    int      m_nextChar;

 protected:

    // Lexical analysis and token handling.  These members need to be
    // protected instead of private since we want to be able to
    // reimplement getNextToken().

    /**
     * The next token to be used in the parser.
     */
    int      m_nextToken;

    // Values for the respective token.  These could be made into a
    // union, but I don't think it is necessary to bother, since they
    // are so few and we don't instantiate a lot of copies of the
    // parser.
    int      m_intVal;		// Valid if m_nextToken == INT_TOKEN
    double   m_floatVal;	// Valid if m_nextToken == FLOAT_TOKEN
};

#endif