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Diffstat (limited to 'kalzium/src/parser.h')
-rw-r--r-- | kalzium/src/parser.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/kalzium/src/parser.h b/kalzium/src/parser.h new file mode 100644 index 00000000..f4ec68e7 --- /dev/null +++ b/kalzium/src/parser.h @@ -0,0 +1,105 @@ +/*************************************************************************** + copyright : (C) 2005 by Inge Wallin + email : inge@lysator.liu.se + ***************************************************************************/ +/*************************************************************************** + * * + * 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 <qstring.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 QString& _str); + ~Parser(); + + /** + * Start a new parse. + */ + void start(const QString& _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: + QString 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 |