Input &nbsp;( Source code for QBASIC language )<BR>
<TEXTAREA   Name=TextArea1   Cols=79   Rows=10   >
   ' Simple program

   PRINT "Hello World..."
</TEXTAREA><BR>


<INPUT   Type=BUTTON   Value="Run parsing process"
   OnClick="JavaScript:var  GI_ParseMode ;

                       var  G_Time1 ;
                       var  G_Time2 ;

                       G_StrParseMe = TextArea1.value ;
                       GI_ParseMode = OutputOpt.value ;

                       //----- OPTIONAL : Parameter 2
                       G_ParseMode = pmVerbose ;
                       if (GI_ParseMode == '/Same')       G_ParseMode = pmSame ;
                       if (GI_ParseMode == '/Verbose')    G_ParseMode = pmVerbose ;
                       if (GI_ParseMode == '/Parse')      G_ParseMode = pmParse ;
                       if (GI_ParseMode == '/NoComment')  G_ParseMode = pmNoComment ;
                       if (GI_ParseMode == '/Compact')    G_ParseMode = pmCompact ;
                       if (GI_ParseMode == '/PackLine')   G_ParseMode = pmPackLine ;

                       document.writeln (   '<XMP>'  +  '***** OUTPUT'   );
                       G_Time1 = new Date();
                       ProcessBuffer ( 0 , null );      //--- Before Process
                       ProcessBuffer ( 0 , G_StrParseMe.length -1 );
                       ProcessBuffer ( null , null );      //--- After Process
                       G_Time2 = new Date();
                       document.writeln (   '*****  '  +  String(G_Time2.valueOf()-G_Time1.valueOf())  +  '  milliseconds'   );
                       document.writeln (   '</XMP>'   );
           "
   > &nbsp;


Output option
<SELECT   Name=OutputOpt   Size=1   >
   <OPTION   Value="/Same"        >/Same</OPTION>
   <OPTION   Value="/Verbose"     SELECTED   >/Verbose</OPTION>
   <OPTION   Value="/Parse"       >/Parse</OPTION>
   <OPTION   Value="/NoComment"   >/NoComment</OPTION>
   <OPTION   Value="/Compact"     >/Compact</OPTION>
   <OPTION   Value="/PackLine"    >/PackLine</OPTION>
</SELECT>





<SCRIPT>
/*
!------------------------------------------------------------------------------
! This file toolbox
!------------------------------------------------------------------------------
*/
/*
!---------------
! Const: Parser Result prXXXXX
!
! NEXTxxx: Mini parser for QBASIC language
!---------------
*/
   var  prToken             = 1 ;
   var  prSymbol            = 2 ;
   var  prSymbol2Ch         = 3 ;
   var  prQuotedText        = 4 ;
   var  prIllegalToken      = 5 ;

   var  prLineComment       = 6 ;
   var  prComment           = 7 ;
   var  prFilling           = 8 ;

   var  prEndQuoteMissing   = 9 ;
   var  prEndCommentMissing = 10 ;
   var  prEndOfBuffer       = 11 ;


   var  C_ParserResultStr = new Array(11-1);
      C_ParserResultStr[0] = 'Token'             ;
      C_ParserResultStr[1] = 'Symbol'            ;
      C_ParserResultStr[2] = 'Symbol2Ch'         ;
      C_ParserResultStr[3] = 'QuotedText'        ;
      C_ParserResultStr[4] = 'IllegalToken'      ;
      C_ParserResultStr[5] = 'LineComment'       ;
      C_ParserResultStr[6] = 'Comment'           ;
      C_ParserResultStr[7] = 'Filling'           ;
      C_ParserResultStr[8] = 'EndQuoteMissing'   ;
      C_ParserResultStr[9] = 'EndCommentMissing' ;
      C_ParserResultStr[10] = 'EndOfBuffer'       ;


//===== NEXTxxx

   var  G_StrParseMe ;
   var  G_PBegin ;
   var  G_PAfterEnd ;

function   NEXTxxx   ( I_BuffPLast
                     , IO_PBegin
                     , O_PAfterEnd
                     )   //Parser Result const, prXXXXX
{
                                                                //   <>   <=   >=

   var  C_OneCharSymbols   = '+-*/>=<(),:\\^;?' ;               //---   _
   var  C_CharsEndingToken = '+-*/>=<(),:\\^;?'  +  '\'' ;      //---   _

   var  L_Ch ;

   //----- Controls : nil, non sense values
   if ((I_BuffPLast == null) || (IO_PBegin == null) || (I_BuffPLast < IO_PBegin))
   {
      return  prEndOfBuffer ;
   }

   G_PBegin = IO_PBegin ;
//DEBUG:document.writeln (   'DEBUG.NEXTxxx.1:'  +  ''   );
//return  prSymbol2Ch ;

   //===== 0. Search first char of the token
   //----- Buffer   :  Other...  CRLF  Other...   TokenBeeingSearched
   //----- Pointers :                     G_PBegin^                  ^G_PAfterEnd
   L_Ch = G_StrParseMe.charAt ( G_PBegin );
   while ((L_Ch == ' ') || (L_Ch == '\x09') || (L_Ch == '\x0A') || (L_Ch == '\x0D'))  {
      G_PBegin++ ;
      if (I_BuffPLast < G_PBegin)  {  return  prEndOfBuffer ;  }
      L_Ch = G_StrParseMe.charAt ( G_PBegin );
   }
   G_PAfterEnd = G_PBegin ;

   do {      //--- PATCH  ( 1 / 2 ) , "Not aloud: goto LABEL_Bloc3"

   //===== 1. Special three non alpha chars tokens, like

   //===== 2. Special two non alpha chars tokens, like   <>   <=   >=

   //----- 2.1. case:   <>
   if (L_Ch == '<')
   {
      G_PAfterEnd++ ;
      if (I_BuffPLast < G_PAfterEnd)                {  G_PAfterEnd--;  break;  }
      if (G_StrParseMe.charAt(G_PAfterEnd) != '>')  {  G_PAfterEnd--;  }
      else  {
         G_PAfterEnd++ ;
         return  prSymbol2Ch ;
      }
   }

   //----- 2.2. case:   <=
   if (L_Ch == '<')
   {
      G_PAfterEnd++ ;
      if (I_BuffPLast < G_PAfterEnd)                {  G_PAfterEnd--;  break;  }
      if (G_StrParseMe.charAt(G_PAfterEnd) != '=')  {  G_PAfterEnd--;  }
      else  {
         G_PAfterEnd++ ;
         return  prSymbol2Ch ;
      }
   }

   //----- 2.3. case:   >=
   if (L_Ch == '>')
   {
      G_PAfterEnd++ ;
      if (I_BuffPLast < G_PAfterEnd)                {  G_PAfterEnd--;  break;  }
      if (G_StrParseMe.charAt(G_PAfterEnd) != '=')  {  G_PAfterEnd--;  }
      else  {
         G_PAfterEnd++ ;
         return  prSymbol2Ch ;
      }
   }

   } while (false);      //--- PATCH  ( 2 / 2 ) , "Not aloud: goto LABEL_Bloc3"

   //===== 3. Other cases
 LABEL_Bloc3:
   //----- 3.1. case:   '... comment
   if (L_Ch == '\'')
   {
      do
      {
         G_PAfterEnd++ ;
         if (I_BuffPLast < G_PAfterEnd)  break ;
         L_Ch = G_StrParseMe.charAt ( G_PAfterEnd );
      } while (!((L_Ch == '\x0A') || (L_Ch == '\x0D')));
      return  prLineComment ;
   }  else

   //----- 3.2. case:   one char symbol,  like + - * < ; etc
   if (C_OneCharSymbols.indexOf(L_Ch) >= 0)
   {
      G_PAfterEnd++ ;
      return  prSymbol ;
   }  else

   //----- 3.3. case:   quote "
   if (L_Ch == '"')
   {
      //----- Buffer  :  Other...  CRLF  Other...   " Quotes beeing processed "
      //----- Pointers:                     G_PBegin^                          ^G_PAfterEnd
      do   // search end quote, skipping double quotes
      {
         G_PAfterEnd++ ;
         if (I_BuffPLast < G_PAfterEnd)             {  return  prEndQuoteMissing ;  }
         L_Ch = G_StrParseMe.charAt ( G_PAfterEnd );
         if ((L_Ch == '\x0A') || (L_Ch == '\x0D'))  {  return  prEndQuoteMissing ;  }
         if (L_Ch == '"')  {
            G_PAfterEnd++ ;
            if (I_BuffPLast < G_PAfterEnd)  {  return  prQuotedText ;  }
            return  prQuotedText ;
         }
      } while (true);
   }  else

   //----- 3.5. case:   normal token
   {
      //----- Buffer   :  Other...  CRLF  Other...   TokenBeeingSearched
      //----- Pointers :                     G_PBegin^                  ^G_PAfterEnd
      do
      {
         G_PAfterEnd++ ;
         if (I_BuffPLast < G_PAfterEnd)  break ;
         L_Ch = G_StrParseMe.charAt ( G_PAfterEnd );
         if (C_CharsEndingToken.indexOf(L_Ch) >= 0)  break ;
      } while (!((L_Ch == ' ') || (L_Ch == '\x09') || (L_Ch == '\x0A') || (L_Ch == '\x0D')));
      return  prToken ;
   }
}

/*
!------------------------------------------------------------------------------
! This file toolbox  ( bis )
!------------------------------------------------------------------------------
*/
/*
!---------------
! ProcessBuffer_Same
! ProcessBuffer_Verbose
! ProcessBuffer_Parse
! ProcessBuffer_NoComment
! ProcessBuffer_Compact
! ProcessBuffer_PackLine
!---------------
*/
//===== ProcessBuffer_Same

function   ProcessBuffer_Same   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_Ch ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      L_Ch = G_StrParseMe.charAt ( L_Ptr );

      //----- LOOP 2.1 , OUTPUT : Filling
      while ((L_Ch == ' ') || (L_Ch == '\x09') || (L_Ch == '\x0A') || (L_Ch == '\x0D'))  {
         document.write (   L_Ch   );
         L_Ptr++ ;
         if (I_BufLast < L_Ptr)  return ;
         L_Ch = G_StrParseMe.charAt ( L_Ptr );
      }//while
//DEBUG:document.writeln (   'DEBUG.1:'  +  String(L_prResult)  +  ':'  +  String(L_Ptr)  +  '-->'  +  String(L_PAfterEnd)   );
//return;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if (   (L_prResult == prToken) || (L_prResult == prSymbol) || (L_prResult == prSymbol2Ch) || (L_prResult == prQuotedText) || (L_prResult == prIllegalToken)
          || (L_prResult == prLineComment) || (L_prResult == prComment))
      {
         //----- LOOP 2. , OUTPUT : Token, Symbol,... as found
         while (L_Ptr < L_PAfterEnd)  {
            L_Ch = G_StrParseMe.charAt ( L_Ptr );
            document.write (   L_Ch   );
            L_Ptr++ ;
         }//while
      }

   } while (L_Ptr <= I_BufLast);
}

//===== ProcessBuffer_Verbose

function   ProcessBuffer_Verbose   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_Ch ;

   var  L_TmpStr ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if (true)  {
         //----- LOOP 2. , OUTPUT : Token, Symbol,... as found
         while (L_Ptr < L_PAfterEnd)  {
            L_Ch = G_StrParseMe.charAt ( L_Ptr );
            document.write (   L_Ch   );
            L_Ptr++ ;
         }//while

         //----- OUTPUT : Token type
         L_TmpStr = C_ParserResultStr[L_prResult-1];
         while (L_TmpStr.length < 11)  {  L_TmpStr = ' '  +  L_TmpStr ;  }
         if (L_TmpStr.length > 11)  L_TmpStr = L_TmpStr.substr ( 0 , 11 );
         document.write (   '   \' '  +  L_TmpStr   );

         document.writeln();
      }

   } while (L_Ptr <= I_BufLast);
}

//===== ProcessBuffer_Parse

function   ProcessBuffer_Parse   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_Ch ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if (   (L_prResult == prToken) || (L_prResult == prSymbol) || (L_prResult == prSymbol2Ch) || (L_prResult == prQuotedText) || (L_prResult == prIllegalToken)
          || (L_prResult == prLineComment) || (L_prResult == prComment))
      {
         //----- LOOP 2. , OUTPUT : Token, Symbol,... as found
         while (L_Ptr < L_PAfterEnd)  {
            L_Ch = G_StrParseMe.charAt ( L_Ptr );
            document.write (   L_Ch   );
            L_Ptr++ ;
         }//while

         document.writeln();
      }

   } while (L_Ptr <= I_BufLast);
}

//===== ProcessBuffer_NoComment

function   ProcessBuffer_NoComment   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_Ch ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if ((L_prResult == prToken) || (L_prResult == prSymbol) || (L_prResult == prSymbol2Ch) || (L_prResult == prQuotedText) || (L_prResult == prIllegalToken))
      {
         //----- LOOP 2. , OUTPUT : Token, Symbol,... as found
         while (L_Ptr < L_PAfterEnd)  {
            L_Ch = G_StrParseMe.charAt ( L_Ptr );
            document.write (   L_Ch   );
            L_Ptr++ ;
         }//while

         document.writeln();
      }

   } while (L_Ptr <= I_BufLast);
}

//===== ProcessBuffer_Compact

   var  G_TmpBuf_LineCompacted ;
   var  G_PREV_prResult ;

function   ProcessBuffer_Compact   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_String0  ;
   var  L_TokenLen ;
   var  L_String1  ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      if (I_BufFirst != null)
      {   // Before Process
         G_TmpBuf_LineCompacted = '' ;
         G_PREV_prResult        = prFilling ;
      }
      else  {   // After Process
         if (G_TmpBuf_LineCompacted != '')
            document.writeln (   G_TmpBuf_LineCompacted   );
      }
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if ((L_prResult == prToken) || (L_prResult == prSymbol) || (L_prResult == prSymbol2Ch) || (L_prResult == prQuotedText) || (L_prResult == prIllegalToken))
      {
         //----- Put a space between 2 tokens ?
         if ((G_PREV_prResult == prToken) && (L_prResult == prToken))
            L_String0 = ' '
         else
            L_String0 = '' ;

         //----- CONTROL : Current token too long ?
         L_TokenLen = L_PAfterEnd - L_Ptr ;
         if (L_TokenLen > 126)  {
            //----- OUTPUT : Previous temp buffer
            document.writeln (   G_TmpBuf_LineCompacted   );
            G_TmpBuf_LineCompacted = '' ;

            //----- OUTPUT : Current token
            L_String1 = G_StrParseMe.substr ( L_Ptr , 126 );
            document.writeln (   L_String1   );

            //----- OUTPUT : Error message
            document.writeln (   'ERROR: '  +  'Token too long.'   );
            return ; //--throw ( 1 );--
         }

         //----- Copy current token ==> TmpString
         L_String1 = G_StrParseMe.substr ( L_Ptr , L_TokenLen );

         //----- "Temp line buffer" would be full ?
         if (( G_TmpBuf_LineCompacted.length + L_String0.length + L_String1.length ) > 79)
         {
            //----- OUTPUT : Previous temp buffer
            document.writeln (   G_TmpBuf_LineCompacted   );
            G_TmpBuf_LineCompacted = '' ;
            L_String0              = '' ;   // Token sent to next line
         }

         //----- Temp line buffer : add "token"
         G_TmpBuf_LineCompacted += L_String0  +  L_String1 ;

         G_PREV_prResult = L_prResult ;
      }

   } while (L_Ptr <= I_BufLast);
}

//===== ProcessBuffer_PackLine

function   ProcessBuffer_PackLine   ( I_BufFirst , I_BufLast )
{
   var  L_Ptr       ;
   var  L_PAfterEnd ;
   var  L_prResult  ;

   var  L_Ch ;

   var  L_NewLineQ ;

   var  L_String0  ;
   var  L_TokenLen ;
   var  L_String1  ;

   if ((I_BufLast == null) || (I_BufFirst == null))  {
      if (I_BufFirst != null)
      {   // Before Process
         G_TmpBuf_LineCompacted = '' ;
         G_PREV_prResult        = prFilling ;
      }
      else  {   // After Process
         if (G_TmpBuf_LineCompacted != '')
            document.writeln (   G_TmpBuf_LineCompacted   );
      }
      return ;
   }

   L_PAfterEnd = I_BufFirst ;

   //----- LOOP 1 , Call parser
   do
   {
      L_Ptr = L_PAfterEnd ;

      L_Ch = G_StrParseMe.charAt ( L_Ptr );

      //----- LOOP 2.1 , Skip filling
      while ((L_Ch == ' ') || (L_Ch == '\x09'))  {
         L_Ptr++ ;
         if (I_BufLast < L_Ptr)  break ;
         L_Ch = G_StrParseMe.charAt ( L_Ptr );
      }//while

      //----- Check NewLine
      if (L_Ch == '\x0A')
      {
         L_Ptr++ ;
         L_NewLineQ = true ;
      }
      else  {
         if (L_Ch == '\x0D')  {
            L_Ptr++ ;
            if (L_Ptr <= I_BufLast)  {
               L_Ch = G_StrParseMe.charAt ( L_Ptr );
               if (L_Ch == '\x0A')
                  L_Ptr++ ;
            }
            L_NewLineQ = true ;
         }
         else
            L_NewLineQ = false ;
      }
      if (L_NewLineQ == true)  {
         //----- OUTPUT : temp line buffer
         if (G_TmpBuf_LineCompacted != '')  {
            document.writeln (   G_TmpBuf_LineCompacted   );
            G_TmpBuf_LineCompacted = '' ;
            G_PREV_prResult        = prFilling ;
         }
      }
      if (I_BufLast < L_Ptr)  break ;

      //----- PARSER , Get "next token"
      L_prResult = NEXTxxx ( I_BufLast , L_Ptr , L_PAfterEnd );  L_Ptr=G_PBegin;  L_PAfterEnd=G_PAfterEnd;

      if ((L_prResult == prToken) || (L_prResult == prSymbol) || (L_prResult == prSymbol2Ch) || (L_prResult == prQuotedText) || (L_prResult == prIllegalToken))
      {
         //----- Put a space between 2 tokens ?
         if ((G_PREV_prResult == prToken) && (L_prResult == prToken))
            L_String0 = ' '
         else
            L_String0 = '' ;

         //----- CONTROL : Current token too long ?
         L_TokenLen = L_PAfterEnd - L_Ptr ;
         if (L_TokenLen > 126)  {
            //----- OUTPUT : Previous temp buffer
            document.writeln (   G_TmpBuf_LineCompacted   );
            G_TmpBuf_LineCompacted = '' ;

            //----- OUTPUT : Current token
            L_String1 = G_StrParseMe.substr ( L_Ptr , 126 );
            document.writeln (   L_String1   );

            //----- OUTPUT : Error message
            document.writeln (   'ERROR: '  +  'Token too long.'   );
            return ; //--throw ( 1 );--
         }

         //----- Copy current token ==> TmpString
         L_String1 = G_StrParseMe.substr ( L_Ptr , L_TokenLen );

         //----- "Temp line buffer" would be full ?
         if (( G_TmpBuf_LineCompacted.length + L_String0.length + L_String1.length ) > 126)
         {
            //----- OUTPUT : Previous temp buffer
            document.writeln (   G_TmpBuf_LineCompacted   );
            G_TmpBuf_LineCompacted = '' ;

            //----- OUTPUT : Current token
            document.writeln (   L_String1   );

            //----- OUTPUT : Error message
            document.writeln (   'ERROR: '  +  'Line too long.'   );
            return ; //--throw ( 1 );--
         }

         //----- Temp line buffer : add "token"
         G_TmpBuf_LineCompacted += L_String0  +  L_String1 ;

         G_PREV_prResult = L_prResult ;
      }

   } while (L_Ptr <= I_BufLast);
}

/*
!------------------------------------------------------------------------------
! This file routines
!------------------------------------------------------------------------------
*/
/*
!---------------
! ProcessBuffer
!---------------
*/
   var  pmSame      = 0 ;
   var  pmVerbose   = 1 ;
   var  pmParse     = 2 ;
   var  pmNoComment = 3 ;
   var  pmCompact   = 4 ;
   var  pmPackLine  = 5 ;

   var  G_ParseMode ;

//===== ProcessBuffer

function   ProcessBuffer   ( I_BufFirst , I_BufLast )
{
   switch (G_ParseMode)  {
      case pmSame      : ProcessBuffer_Same      ( I_BufFirst , I_BufLast );  break;
      case pmVerbose   : ProcessBuffer_Verbose   ( I_BufFirst , I_BufLast );  break;
      case pmParse     : ProcessBuffer_Parse     ( I_BufFirst , I_BufLast );  break;
      case pmNoComment : ProcessBuffer_NoComment ( I_BufFirst , I_BufLast );  break;
      case pmCompact   : ProcessBuffer_Compact   ( I_BufFirst , I_BufLast );  break;
      case pmPackLine  : ProcessBuffer_PackLine  ( I_BufFirst , I_BufLast );  break;
   }//switch

   /*
   if ((I_BufLast == null) || (I_BufFirst == null))  {
      if (I_BufFirst != null)
         document.writeln (   '***** Begin'   )       //--- Before Process
      else
         document.writeln (   '***** End'     );      //--- After Process
      return ;
   }

   //----- Input ==> Output, char by char
   L_Ptr = I_BufFirst ;
   while (L_Ptr <= I_BufLast)  {
      L_Ch = G_StrParseMe.charAt ( L_Ptr );
      document.write (   L_Ch   );
      L_Ptr++ ;
   }
   */
}
</SCRIPT>