source: trunk/essentials/sys-devel/flex/FlexLexer.h@ 3116

// -*-C++-*-
// FlexLexer.h -- define interfaces for lexical analyzer classes generated
// by flex

// Copyright (c) 1993 The Regents of the University of California.
// All rights reserved.
//
// This code is derived from software contributed to Berkeley by
// Kent Williams and Tom Epperly.
//
//  Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions
//  are met:

//  1. Redistributions of source code must retain the above copyright
//  notice, this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright
//  notice, this list of conditions and the following disclaimer in the
//  documentation and/or other materials provided with the distribution.

//  Neither the name of the University nor the names of its contributors
//  may be used to endorse or promote products derived from this software
//  without specific prior written permission.

//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
//  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
//  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
//  PURPOSE.

// This file defines FlexLexer, an abstract class which specifies the
// external interface provided to flex C++ lexer objects, and yyFlexLexer,
// which defines a particular lexer class.
//
// If you want to create multiple lexer classes, you use the -P flag
// to rename each yyFlexLexer to some other xxFlexLexer.  You then
// include <FlexLexer.h> in your other sources once per lexer class:
//
//      #undef yyFlexLexer
//      #define yyFlexLexer xxFlexLexer
//      #include <FlexLexer.h>
//
//      #undef yyFlexLexer
//      #define yyFlexLexer zzFlexLexer
//      #include <FlexLexer.h>
//      ...

#ifndef __FLEX_LEXER_H
// Never included before - need to define base class.
#define __FLEX_LEXER_H

#include <iostream>
#  ifndef FLEX_STD
#    define FLEX_STD std::
#  endif

extern "C++" {

struct yy_buffer_state;
typedef int yy_state_type;

class FlexLexer {
public:
        virtual ~FlexLexer()    { }

        const char* YYText()    { return yytext; }
        int YYLeng()            { return yyleng; }

        virtual void
                yy_switch_to_buffer( struct yy_buffer_state* new_buffer ) = 0;
        virtual struct yy_buffer_state*
                yy_create_buffer( FLEX_STD istream* s, int size ) = 0;
        virtual void yy_delete_buffer( struct yy_buffer_state* b ) = 0;
        virtual void yyrestart( FLEX_STD istream* s ) = 0;

        virtual int yylex() = 0;

        // Call yylex with new input/output sources.
        int yylex( FLEX_STD istream* new_in, FLEX_STD ostream* new_out = 0 )
                {
                switch_streams( new_in, new_out );
                return yylex();
                }

        // Switch to new input/output streams.  A nil stream pointer
        // indicates "keep the current one".
        virtual void switch_streams( FLEX_STD istream* new_in = 0,
                                        FLEX_STD ostream* new_out = 0 ) = 0;

        int lineno() const              { return yylineno; }

        int debug() const               { return yy_flex_debug; }
        void set_debug( int flag )      { yy_flex_debug = flag; }

protected:
        char* yytext;