TokenTypes CMathParser::NextToken()//{ Gets the next Token from the Input stream } { CSPString NumString;// : String[80]; WORD TLen, NumLen; //, FormLen, Place; // int Check ;//: Integer; char Ch;//, FirstChar; BOOL Decimal ; TokenTypes ResultNextToken; while ((Position < FInput.GetLength()) && (FInput.GetAt(Position) == ' ')) Position++; TokenLen = Position; if (Position >= FInput.GetLength()) { ResultNextToken = EOL; TokenLen = 0; return ResultNextToken; } FInput.MakeUpper(); Ch = FInput.GetAt(Position); if (Ch== '!') { ResultNextToken = ERR; TokenLen = 0; return ResultNextToken ; } if((Ch >= '0' && Ch <= '9') || Ch == '.')// if Ch in ['0'..'9', '.'] then { NumString = ""; TLen = Position; Decimal = FALSE; while ((TLen < FInput.GetLength()) && ((FInput.GetAt(TLen) >= '0' && FInput.GetAt(TLen) <= '9' ) || ((FInput.GetAt(TLen) == '.') && (!Decimal)))) { NumString = NumString + FInput.GetAt(TLen); if (Ch == '.')// then Decimal = TRUE; TLen++;//Inc(TLen); } if ((TLen == 2) && (Ch == '.'))// then { ResultNextToken = BAD; TokenLen = 0; return ResultNextToken ; } if ((TLen < FInput.GetLength()) && ((FInput.GetAt(TLen)) == 'E'))// then { NumString = NumString + 'E'; TLen++; if( FInput.GetAt(TLen) == '+' || FInput.GetAt(TLen) == '-')// in ['+', '-'] then { NumString.SetAt(TLen, FInput.GetAt(TLen));//= NumString + FInput[TLen]; TLen++; } NumLen = 1; while ((TLen < FInput.GetLength()) && (FInput.GetAt(TLen) >= '0' && FInput.GetAt(TLen) <= '9') && (NumLen <= MP_MaxExpLen)) { NumString = NumString + FInput.GetAt(TLen); NumLen++;//Inc(NumLen); TLen++;//Inc(TLen); } } if (NumString[0] == '.')// then NumString = '0' + NumString; CurrToken.Value = atof(NumString); //Val(NumString, CurrToken.Value, Check); /*//if (Check != 0 ) {// begin ErrorCode = MP_ErrMath; ErrorCode = ErrInvalidNum; Position += Pred(Check); //Inc(Position, Pred(Check)); }// end { if } else*/ {// begin ResultNextToken = NUM; Position += NumString.GetLength(); //Inc(Position, System.Length(NumString)); TokenLen = Position - TokenLen; }// end; { else } return ResultNextToken; }//end { if } else if ((Ch>='a' && Ch <= 'z') || (Ch>='A' && Ch <= 'Z'))//in Letters then {// begin if (IsFunc("ABS") || IsFunc("ATAN") || IsFunc("COS") || IsFunc("EXP") || IsFunc("LN") || IsFunc("ROUND") || IsFunc("SIN") || IsFunc("SQRT") || IsFunc("SQR") || IsFunc("TRUNC")|| IsFunc("NOT")||// then//EXPAND IsFunc("BOOL")|| IsFunc("SGN") ) { ResultNextToken = FUNC; TokenLen = Position - TokenLen; return ResultNextToken ; } if (IsFunc("MOD")) { ResultNextToken = MODU; TokenLen = Position - TokenLen; return ResultNextToken ; } if (IsVar(CurrToken.Value)) { ResultNextToken = NUM; TokenLen = Position - TokenLen; return ResultNextToken; } else { ResultNextToken = BAD; TokenLen = 0; return ResultNextToken ; } } else {// begin switch(Ch) { case '+' : ResultNextToken = PLUS; break; case '-' : ResultNextToken = MINUS; break; case '*' : ResultNextToken = TIMES; break; case '/' : ResultNextToken = DIVIDE; break; case '^' : ResultNextToken = EXPO; break; case '(' : ResultNextToken = OPAREN; break; case ')' : ResultNextToken = CPAREN; break; default: ResultNextToken = BAD; TokenLen = 0; return ResultNextToken ; }//end; { case } Position++; TokenLen = Position - TokenLen; return ResultNextToken ; }//end; { else if } }//end; { NextToken }