vos/corelibs/typechain/tclexer.hh

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/** @file tclexer.h Defines TypechainLexer class.
    @author Reed Hedges <reed@zerohour.net>

    Copyright (C) 2002 Reed Hedges

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
*/

#ifndef _TCLEXER_HH_
#define _TCLEXER_HH_

#include <stdio.h>
#include <string>
#include <map>
#include <iostream>

#ifdef USE_STRSTREAM
#include <strstream>
#else
#include <sstream>
#endif

using namespace std;

#ifndef yyFlexLexer
#define yyFlexLexer tcFlexLexer
#include <FlexLexer.h>
#endif

/**
    This class is a yyFlexLexer subclass
    with two pure virtual methods you can override to process
    identifiers and final types:

        void complete_token(string token, map<string,string> params);

    This method is called whenever a complete identifier token has
    been parsed, with parameters (which will have no contents if there
    were no parameters. If a key was supplied with no value, the key
    will be present with an empty string for value. If an empty identifier
    was given (e.g. "foo;;bar;baz") then this method will be called with
    an empty string for token (you may then issue an error, warning, or
    simply ignore it, as you wish).  Reserved identifiers (such as "type")
    are also passed to this method.

        void final_type(string token, map<string,string> params);

    This method is called once for the final media type identifer
    token has been parsed, with parameters, analagous to complete_token.


*/

class TypechainLexer : public yyFlexLexer {

protected:
    string token;
    map<string, string> params;
    char *lastkey;
    string typestring;

    inline void clear_vars() {
        params.clear();
        token = "";
        if (lastkey != 0) free(lastkey);
        lastkey = 0;
    }

public:

    /** Constructor.
        @param typestring   The type string.
    */
    TypechainLexer(const string& typestr) : yyFlexLexer(), lastkey(0) {
        typestring = typestr;
        switch_streams(
#ifdef USE_STRSTREAM
                new istrstream(typestring.c_str(), typestring.length())
#else
                new istringstream(typestring)
#endif
        , 0);
    }


    /** Override this in your subclass to take action on a token. */
    virtual void complete_token(string token, map<string, string> params) = 0;

    /** Override this in your subclass to take action on the final type token. */
    virtual void final_type(string token, map<string, string> params) = 0;

    /** Call this to do the scan */
    int yylex() ;
};

#endif

---