Exemplo n.º 1
0
void processLine(string line, Program & program, EvalState & state) {
   TokenScanner scanner;
   scanner.ignoreWhitespace();
   scanner.scanNumbers();
   scanner.setInput(line);
//   Expression *exp = parseExp(scanner);
//   int value = exp->eval(state);
//   cout << value << endl;
//   delete exp;
   if (!scanner.hasMoreTokens()) {
       return;
   }
   string firstToken = toUpperCase(scanner.nextToken());
   if (firstToken == "RUN") {
       runProgram(program, state);
   }
   else if (firstToken == "QUIT") {
       exit(0);
   }
   else if (firstToken == "HELP") {
       dspHelp();
   }
   else if (firstToken == "CLEAR") {
       program.clear();
   }
   else if (firstToken == "LIST") {
       listCmd(program);
   }
   else if (firstToken == "INPUT" || firstToken == "PRINT" || firstToken == "LET") {
       scanner.saveToken(firstToken);
       Statement * stmt = parseStatement(scanner);
       stmt->execute(state);
       delete stmt;
   }
   else {
       int lineNumber = stringToInteger(firstToken);
       if (!scanner.hasMoreTokens()) {
           program.removeSourceLine(lineNumber);
       }
       else {
           int length = firstToken.length();
           string source = line.substr(length);
           program.addSourceLine(lineNumber, source);
           Statement * stmt = parseStatement(scanner);
           program.setParsedStatement(lineNumber, stmt);
       }
   }
}
/* Function: sqrtFunction()
 * -------------------------
 * Library sqrt function execution. Expects for brackets and involves
 * formulaStringScanning process for expression in brackets. Return sqrt function result
 * for obtained value in brackets.
 *
 * @param scanner   TokenScanner for user formula */
double sqrtFunction(TokenScanner& scanner) {
    bool sqrtFailFlag = false;
    string token = "";
    double sqrtParam = 0;

    if (scanner.hasMoreTokens()) {
        token = scanner.nextToken();//waiting for brackets at this place
        if (token == "(") {
            bool bracketsOpened = true;
            /* Calls internal scanFormulaString process for expression in brackets */
            sqrtParam = scanFormulaString(scanner, bracketsOpened);
        } else {
            sqrtFailFlag = true;
        }
    }

    if (sqrtFailFlag) {
        cout << "   - SQRT FUNCTION FAULT" << endl;
        FAIL_FLAG = true;
        return 0;
    }

    /* Returns sqrt function result */
    return sqrt(sqrtParam);
}
Exemplo n.º 3
0
/**
 * Receive information from file, processes and displays the result on the screen.
 */
void processText(TokenScanner & scanner){
    int counterSentences = 0;
    int counterWords = 0;
    int counterSyllable = 0;
    double grade = 0.0;

    scanner.ignoreWhitespace(); // ignores spaces
    scanner.addWordCharacters("'"); // does part of the token is the character "'"

    // processes each token
    while (scanner.hasMoreTokens()){
        string token = scanner.nextToken();
        counterSentences += checkSentences(token);
        if(checkWords(token)){
            counterWords ++;
            counterSyllable += colSyllable(token);
        }
    }
    // If the file does not contain any words or sentences, assume that their one
    if(counterWords == 0 || counterSentences == 0) counterSentences = counterWords = 1;

    grade = getGrade(counterSentences, counterWords, counterSyllable);

    cout << "Words : " << counterWords << endl;
    cout << "Syllable : " << counterSyllable << endl;
    cout << "Sentences : " << counterSentences << endl;
    cout << "Grade : " << grade << endl;
}
Exemplo n.º 4
0
bool isHaiku(string filename) {
    fstream infile;
    infile.open(filename.c_str());
    string temp;
    int count = 0;
    TokenScanner scanner;
    while(getline(infile, temp)){
        count++;
        int syllables = 0;
        scanner.setInput(temp);
        while (scanner.hasMoreTokens()){
            syllables += syllablesIn(scanner.nextToken());
        }
        if((count == 1 || count ==3)&&syllables!=5){
            infile.close();
            return false;
        }
        if (count == 2 && syllables !=7){
            infile.close();
            return false;
        }
        if (count >3){
            infile.close();
            return false;
        }
            
    }
    return true;
}
/* Function: powFunction()
 * Usage: is called by formulaStringScanning() function if it detect pow token in formula
 * -----------------------------------------------------------------------------------------//
 * Library pow function execution. Believe that it's normalized function -
 * without any variables like "x" or "y" - just pow(<value>, <power for value>):
 * pow(2, 4) = 16
 * Expects brackets, and return pow function result for values in brackets.
 *
 * @param scanner      TokenScanner for user formula */
double powFunction(TokenScanner& scanner) {
    bool powFail = false;
    string token = "";
    string num1 = "";
    string num2 = "";
    while(scanner.hasMoreTokens()) {
        token = scanner.nextToken();//waiting for brackets at this place
        if(token == "(") {
            num1 = scanner.nextToken();//pow function param1
            token = scanner.nextToken();//waiting coma at this place
            if(token == ",") {
                num2 = scanner.nextToken();//pow function param2
                token = scanner.nextToken();//waiting for brackets at this place
                if(token == ")") {
                    break;
                } else {
                    powFail = true;
                }
            } else {
                powFail = true;
            }
        } else {
            powFail = true;
        }

        if(powFail) {
            cout <<  "   - POW FUNCTION INPUT FAULT!" << endl;
            failFlag = true;
            return 0;
        }
    }
    /* Returns pow function result */
    return pow(stringToDouble(num1), stringToDouble(num2));
}
/* Function: sqrtFunction()
 * Usage: is called by formulaStringScanning() function if it detect sqrt token in formula
 * -----------------------------------------------------------------------------------------//
 * Library sqrt function execution. Expects for brackets and involves
 * formulaStringScanning process for expression in brackets. Return sqrt function result
 * for obtained value in brackets.
 *
 * @param scanner   TokenScanner for user formula
 * @param xValue    Value for x variable in user equation */
double sqrtFunction(TokenScanner& scanner, double xValue) {
    bool sqrtFail = false;
    string token = "";
    double num1 = 0;
    if(scanner.hasMoreTokens()) {
        token = scanner.nextToken();
        if(token == "(") { //waiting for brackets at this place
            bool bracketsOpened = true;
            /* Calls internal formulaStringScanning process for expression in brackets */
            num1 = formulaStringScanning(scanner,
                                         bracketsOpened,
                                         xValue);
        } else {
            sqrtFail = true;
        }
    }

    if(sqrtFail) {
        cout << "   - SQRT FUNCTION FAULT" << endl;
        failFlag = true;
        return 0;
    }

    /* Returns sqrt function result */
    return sqrt(num1);
}
Exemplo n.º 7
0
/*
 * Implementation notes: the InputStmt subclass
 * ----------------------------------------------
 * Instances of this class read the identifier from the scanner and notify
 * the user if its format is illegal. In the execute method, it records
 * the input of the user as the value of the identifier in "state".
 */
InputStmt::InputStmt(TokenScanner & scanner){
    string nextToken = scanner.nextToken();
    if (isdigit(nextToken[0]))
        error("Invalid identifier for Input Statement -- can't start with an integer.");
    if (scanner.hasMoreTokens())
        error("Unexpected token: " + scanner.nextToken());
    identifier = nextToken;
}
Exemplo n.º 8
0
LetStmt::LetStmt(TokenScanner &scanner) {
    identifier = scanner.nextToken();
    op = scanner.nextToken();
    exp = readE(scanner, 0);
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}
Exemplo n.º 9
0
/*
 * Function: listProgram
 * Usage: listProgram(program, scanner);
 * -------------------------------------------
 * Displays the lines of the program.  It calls either version of program.toString()
 * depending on whether the user specifies line numbers.
 */
void listProgram(Program & program, TokenScanner & scanner) {
    if (!scanner.hasMoreTokens()) {
        program.toString();
    }
    else {
        int startLine = stringToInteger(scanner.nextToken());
        scanner.nextToken();
        int endLine = stringToInteger(scanner.nextToken());
        program.toString(startLine, endLine);
    }
}
Exemplo n.º 10
0
IfStmt::IfStmt(TokenScanner &scanner) {
    lhs = readE(scanner, 0);
    op = scanner.nextToken();
    rhs = readE(scanner, 0);
    if (scanner.nextToken() != "THEN") {
        error("Syntax error! Invalid IF statement!");
    }
    nextLine = stringToInteger(scanner.nextToken());
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}
Exemplo n.º 11
0
void processLine(string line, Program & program, EvaluationContext & context) {
   TokenScanner scanner;
   scanner.ignoreWhitespace();
   scanner.setInput(line);
    
    string firstToken = toUpperCase(scanner.nextToken());
    if (firstToken == "RUN") {
        runProgram(program, context);
    }
    else if (firstToken == "LIST") {
        listProgram(program, scanner);
    }
    else if (firstToken == "CLEAR") {
        program.clear();
    }
    else if (firstToken == "HELP") {
        if (!scanner.hasMoreTokens()) {
            displayHelp();
        }
        else {
            specificHelp(scanner);
        }
    }
    else if (firstToken == "QUIT") {
        exit(0);
    }
    else {
        int lineNumber = stringToInteger(firstToken);
        if (!scanner.hasMoreTokens()) {
            program.removeSourceLine(lineNumber);
        }
        else {
            Statement *stmt = parseStatement(scanner);
            program.addSourceLine(lineNumber, line);
            program.setParsedStatement(lineNumber, stmt);
        }
    }
}
void toAlpha(std::string word, Map<std::string, std::string>& symbolTable) {
	TokenScanner scanner;
	scanner.ignoreWhitespace();

	for(char i = 'A'; i < 'Z'; i++)
		scanner.addWordCharacters(symbolTable.get(charToString(i)));

	scanner.setInput(word);

	while(scanner.hasMoreTokens()) {
		std::string symbol = scanner.nextToken();
		cout << symbolTable.get(symbol);
	}
	cout << endl;
}
void interpreter(void) {
	std::string line;
	TokenScanner scanner;
	scanner.ignoreWhitespace();
	scanner.scanNumbers();
	Map<std::string, std::string> symbolTable;

	cout << "Interpreter is running: " << endl;

	// Main loop:
	std::string key, value;
	while(true) {
		cout << "> ";
		line = getLine();

		if(line == "quit")
			break;

		else if(line == "list") {
			for(std::string key : symbolTable) {
				cout << key << " = " << symbolTable.get(key) << endl;
			}
		}

		else if(symbolTable.containsKey(line))
			cout << symbolTable.get(line) << endl;

		// Parse statements:
		else {
			scanner.setInput(line);
			bool isValue = false;
			while(scanner.hasMoreTokens()) {
				std::string token = scanner.nextToken();
				if(isValue)
					value = token;
				else if(token == "=")
					isValue = true;
				else
					key = token;
			}
			symbolTable.add(key, value);
		}
	}

	cout << "Interpreter is stopped." << endl;
}
/* Function: powFunction()
 * ------------------------
 * Library pow function execution. Expects sequentally:
 * - brackets, param1, coma, param2, brackets.
 *
 * @param scanner      TokenScanner for user formula */
double powFunction(TokenScanner& scanner) {
    bool powFailFlag = false;
    string token = "";
    string powParam_1 = "";     //pow function param1
    string powParam_2 = "";     //pow function param2
    while (scanner.hasMoreTokens()) {
        token = scanner.nextToken();//waiting for brackets at this place
        if (token == "(") {
            powParam_1 = scanner.nextToken();
            token = scanner.nextToken();//waiting for coma at this place
            if (token == ",") {
                powParam_2 = scanner.nextToken();
                token = scanner.nextToken();//waiting for brackets - end of pow params input
                if (token == ")") {
                    break;
                } else {
                    powFailFlag = true;
                }
            } else {
                powFailFlag = true;
            }
        } else {
            powFailFlag = true;
        }

        if (powFailFlag) {
            cout << "   - POW FUNCTION INPUT FAULT!" << endl;
            FAIL_FLAG = true;
            return 0;
        }
    }

    /* Returns pow function result */
    double param1 = stringToDouble(powParam_1);
    double param2 = stringToDouble(powParam_2);
    return pow(param1, param2);
}
/* Function: scanFormulaString()
 * -----------------------------
 * Recursively scanns formula string and sorts each token through stacks due to shunting-yard
 * algorithm. If "()" appear in this recursion  it controls brackets condition. Detects two
 * pow, sqrt - additional library function in user  formula. Breaks process due to global
 * failFlag. Returns double of calculated result. In case of process faults zero result
 * is returned, and fail message is shown.
 *
 * @param scanner               Scanner for main formula string
 * @param bracketsOpenedBefore  Brackets were opened before this recursion invocation */
double scanFormulaString(TokenScanner& scanner, bool& bracketsOpenedBefore) {
    if (FAIL_FLAG) {
        return 0;  //Global flag apearance
    }

    Stack<double> numbersStack; //Stacks for Shunting-Yard process
    Stack<string> operatorsStack; //in current recursion invocation
    string token = "";
    bool bracketsOpenedHere = false;//Rises if "(" appear in this recursion

    /* Main string scanning. It stops due to conditions:
     * - end of formula string
     * - closed brackets condition
     * - FAIL_FLAG appearance                       */
    while (scanner.hasMoreTokens()) {
        token = scanner.nextToken();

        if (token == "pow") {
            /* Lunches library pow function process  */
            double powResult = powFunction(scanner);
            numbersStack.push(powResult);
        }else if (token == "sqrt") {
            /* Lunches library sqrt function process  */
            double sqrtResult = sqrtFunction(scanner);
            numbersStack.push(sqrtResult);
        }else{//Numbers, brackets or garbage symbol occur cases
            if (token == "(") {
                bracketsOpenedHere = true;
                /* Calls new formula recursion for this scanner */
                numbersStack.push(scanFormulaString(scanner, bracketsOpenedHere));
            }else if (token == ")") {
                if (bracketsOpenedBefore) { //Brackets are closed correctly
                    bracketsOpenedBefore = false;//it is end of this recursion
                    break;
                }else  {//Token is ")" and no bracketsOpenedBefore flag
                    FAIL_FLAG = true; //Brackets weren't opened
                    cout << "   - NOT OPENED BRACKETS! " << endl;
                    break;   //Break to show  error to user
                }
            }else {
                if (FAIL_FLAG) {
                    break;//Break if some faults appear in this recursion
                }
                /* Call Shunting-Yard sorting for this token  */
                sortTokenByStacks(token, numbersStack, operatorsStack);
            }
        }
    }//End of while(scanner.hasMoreTokens())

    /* Shunting-yard final calculation */
    if (bracketsOpenedBefore) {//If brackets haven't been closed in this recursion
        cout << "   - NOT CLOSED BRACKETS! " << endl;
        FAIL_FLAG = true;
        return 0;
    } else {
        if (FAIL_FLAG) {//Main scanning cycle was breaked by some faults
            return 0;
        } else {
            /* Final stacks processing */
            return getFinalStacksResult(numbersStack, operatorsStack);
        }
    }
}
Exemplo n.º 16
0
InputStmt::InputStmt(TokenScanner &scanner) {
    identifier = scanner.nextToken();
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}
/* Function: formulaStringScanning()
 * -----------------------------------------------------------------------------------------//
 * Recursively scanns formula string and sorts each token through stacks due to shunting-yard
 * algorithm. If "()" appear in this recursion  it controls brackets condition. Detects two
 * pow, sqrt - additional library function in user  formula. Breaks process due to global
 * failFlag. Returns double of calculated result. In case of process faults zero result
 * is returned, and fail message is shown.
 *
 * @param scanner               Scanner for main formula string
 * @param bracketsOpenedBefore  Brackets were opened before this recursion invocation
 * @param xValue                Value for x variable in user equation */
double formulaStringScanning(TokenScanner& scanner,
                             bool &bracketsOpenedBefore,
                             double xValue) {
    if(failFlag) {
        return 0;   //Global flag apearance
    }
    else {
        MyStack<double> stackNumbers;//Stacks for current recursion invocation
        MyStack<string> stackOperators;
        string token = "";
        bool bracketsOpenedHere = false;//Rises if "(" appear in this recursion
        while(scanner.hasMoreTokens()) {
            token = scanner.nextToken();
            if(token == "x") {
                /* Sabstitute x-token by user xValue param */
                stackNumbers.push(xValue);
            }
            else if(token == "pow") {
                /* Lunches library pow function process  */
                stackNumbers.push(powFunction(scanner));
            } else if(token == "sqrt") {
                /* Lunches library sqrt function process  */
                stackNumbers.push(sqrtFunction(scanner, xValue));
            } else { //Brackets case
                if(token == "(") {
                    bracketsOpenedHere = true;
                    /* Calls new formula recursion for this scanner */
                    stackNumbers.push(formulaStringScanning(scanner,
                                                            bracketsOpenedHere,
                                                            xValue));
                } else if(token == ")") {
                    if(bracketsOpenedBefore) {       //Brackets are closed correctly
                        bracketsOpenedBefore = false;//it is end of this recursion
                        break;
                    }
                    else {      //Token is ")" and no bracketsOpenedBefore flag
                        failFlag = true;        //Brackets were opened
                        cout <<  "   - NOT OPENED BRACKETS! " << endl;
                        break;                  //Break to show  error to user
                    }
                } else {
                    if(failFlag)break;
                    /* If no fails, and token is valid - lunches
                     * Shunting-Yard sorting  */
                    sortTokenByStacks(token, stackNumbers, stackOperators);
                }
            }//End of Brackets case else statement
        }//End of while(scanner.hasMoreTokens())

        /* Shunting-yard final calculation */
        if(bracketsOpenedBefore) { //If brackets haven't been closed in this recursion
            cout <<  "   - NOT CLOSED BRACKETS! " << endl;
            failFlag = true;
            return 0;
        } else {
            if(failFlag) { //There were some other fails
                return 0;
            } else {
                /* Calculate main result, due to stacks, for current calculation stage. */
                return getFinalStacksResult(stackNumbers, stackOperators);
            }
        }
    }//End of else statement (no failFlag at recursion start)
}
Exemplo n.º 18
0
void processLine(string line, Program & program, EvalState & state) {
  /* TokenScanner scanner;
   scanner.ignoreWhitespace();
   scanner.scanNumbers();
   scanner.setInput(line);
   Expression *exp = parseExp(scanner);
   int value = exp->eval(state);
   cout << value << endl;
   delete exp;*/

   TokenScanner scanner;
   scanner.ignoreWhitespace();
   scanner.scanNumbers();
   scanner.setInput(line);
   string token = scanner.nextToken();
   TokenType type = scanner.getTokenType(token);
   if (type == WORD){
	   if (token == "RUN")
	   {
		   int current_line=program.getFirstLineNumber();
		   while (current_line>=0)
		   {
			   int next_line = program.getNextLineNumber(current_line);
			   Statement* stat=program.getParsedStatement(current_line);
			   StatementType type = stat->get_type();
			   if (type == END)
				   break;
			   if (type == GOTO)
			   {
				   ((Gotostmt*)stat)->execute(state,current_line);
				   
				   continue;
			   }
			   if (type == IF)
			   {
				   ((Ifstmt*)stat)->execute(state, current_line);
				   if (current_line != -2)
			  	       continue;
			   }
			  
			   stat->execute(state);
			   current_line = next_line;
		   }
		  
	   }
	   if (token == "QUIT")
	   {
		   exit(0);
	   }
	   if (token == "CLEAR")
	   {
		   program.clear();
		   EvalState state1;
		   state = state1;
		   
	   }
	   if (token == "HELP")
	   {
	   }
	   if (token == "LIST")
	   {
		   int current_line = program.getFirstLineNumber();
		   while (current_line != -1)
		   {
			   cout << program.getSourceLine(current_line) << endl;
			   current_line = program.getNextLineNumber(current_line);
		   }
	   }
	   if (token == "INPUT"){
		   string st = scanner.nextToken();
		   if (scanner.hasMoreTokens())
			   error("SYNTAX ERROR");
		   Inputstmt inputst(st);
		   inputst.execute(state);
		  
	   }
	   if (token == "PRINT"){
		   Printstmt printst(scanner);
		   printst.execute(state);
	   }

	   if (token == "LET")
	   {
		   Letstmt lets(scanner);
		   lets.execute(state);
		 
	   }
	   if (token != "RUN"&&token != "CLEAR"&&token != "HELP"&&token != "LIST"&&token != "QUIT"&&token != "PRINT"&&token != "LET"&&token != "INPUT")
		   error("SYNTAX ERROR");
   }


   else if (type == NUMBER){
	   int line_num = atoi(token.c_str());
	   
	   string token2 = scanner.nextToken();
	   if (token2 == "")
	   {
		   program.removeSourceLine(line_num);
		   return;
	   }
	   if (token2 == "REM")
	   {
		   string str, temp;
		   while (scanner.hasMoreTokens())
		   {
			   temp = scanner.nextToken();
			   str += temp;
		   }
		   Statement* remst = new Remstmt(str);
		   program.setParsedStatement(line_num, remst);
		   program.addSourceLine(line_num, line);
		   return;
	   }

	   if (token2 == "LET")
	   {
		   Statement *letst = new Letstmt(scanner);
		   program.setParsedStatement(line_num, letst);
		   program.addSourceLine(line_num, line);
		   return;
	   }

	   if (token2 == "PRINT")
	   {
		   Statement *printst = new Printstmt(scanner);
		   program.setParsedStatement(line_num, printst);
		   program.addSourceLine(line_num, line);
		   return;
	   }

	   if (token2 == "INPUT")
	   {
		   string st = scanner.nextToken();
		   if (scanner.hasMoreTokens())
			   error("SYNTAX ERROR");
		   Statement* inputstat = new Inputstmt(st);
		   program.setParsedStatement(line_num, inputstat);
		   program.addSourceLine(line_num, line);
		   return;
	   }
	   if (token2 == "GOTO")
	   {
		   string token_tmp = scanner.nextToken();
		   TokenType type = scanner.getTokenType(token_tmp);
		   if (type != NUMBER)
			   error("SYNTAX ERROR");
		   if (scanner.hasMoreTokens())
			   error("SYNTAX ERROR");
		   int linenum = atoi(token_tmp.c_str());
		   Statement* gotostat = new Gotostmt(linenum);
		   program.setParsedStatement(line_num, gotostat);
		   program.addSourceLine(line_num, line);
		   return;
	   }


	   if (token2 == "IF")
	   {
		   TokenScanner Lscanner;
		   TokenScanner Rscanner;
		   string left, right, tmp, cmp;
		   while (scanner.hasMoreTokens())
		   {
			   tmp = scanner.nextToken();
			   if (tmp == "=" || tmp == ">" || tmp == "<")
			   {
				   cmp = tmp;
				   break;
			   }

			   else left = left + tmp;
		   }
		   if (cmp != "="&&cmp != "<"&&cmp != ">")
			   error("SYNTAX ERROR");

		   while (scanner.hasMoreTokens())
		   {
			   tmp = scanner.nextToken();
			   if (tmp == "THEN")
				   break;
			   else right = right + tmp;
		   }
		   if (tmp != "THEN")
			   error("SYNTAX ERROR");

		   string token_tmp = scanner.nextToken();
		   TokenType type = scanner.getTokenType(token_tmp);
		   if (type != NUMBER)
			   error("SYNTAX ERROR");
		   if (scanner.hasMoreTokens())
			   error("SYNTAX ERROR");
		   int linenum = atoi(token_tmp.c_str());

		   Lscanner.setInput(left);
		   Rscanner.setInput(right);
		   Expression *lexp = parseExp(Lscanner);
		   Expression *rexp = parseExp(Rscanner);

		   Statement* ifstat = new Ifstmt(lexp, rexp, cmp, linenum);
		   program.setParsedStatement(line_num, ifstat);
		   program.addSourceLine(line_num, line);
		   return;
	   }
	   if (token2 == "END")
	   {
		   Statement* endstat=new Endstmt();
		   program.setParsedStatement(line_num, endstat);
		   program.addSourceLine(line_num, line);
		   return;
	   }

	   
	    error("SYNTAX ERROR");
	  

   }
    else   error("SYNTAX ERROR");
}
Exemplo n.º 19
0
/*
 * Function: processLine
 * Usage: processLine(line, program, state);
 * -----------------------------------------
 * Processes a single line entered by the user.  In this version,
 * the implementation does exactly what the interpreter program
 * does in Chapter 19: read a line, parse it as an expression,
 * and then print the result.  In your implementation, you will
 * need to replace this method with one that can respond correctly
 * when the user enters a program line (which begins with a number)
 * or one of the BASIC commands, such as LIST or RUN.
 */
void processLine(string line, Program & program, EvalState & state) {
   TokenScanner scanner;
   scanner.ignoreWhitespace();
   scanner.scanNumbers();
   scanner.setInput(line);
   string token=scanner.nextToken();
   TokenType type=scanner.getTokenType(token);
   int lineNumb;
   int priorLineNumb;
   if(type==NUMBER){
     if(scanner.hasMoreTokens()){
       program.addSourceLine(stringToInteger(token),line);
       Statement *stmt=parseStatement(scanner); 
       program.setParsedStatement(stringToInteger(token),stmt);  //link statement to line number
     }
     else
       program.removeSourceLine(stringToInteger(token));
   }
   if(type==WORD){
     if(token=="LIST"){
       lineNumb=program.getFirstLineNumber();
       while(lineNumb!=-1){
	 cout<<program.getSourceLine(lineNumb)<<endl;
	 lineNumb=program.getNextLineNumber(lineNumb);
       }
     }
     else if(token=="RUN"){
       state.setCurrentLine(program.getFirstLineNumber());
       lineNumb=state.getCurrentLine();
       while(lineNumb!=-1){	 
	 if(program.hasLineNumber(lineNumb)==false)
	   error("Invalid line reference at program line "+integerToString(priorLineNumb));
	 Statement *stmt=program.getParsedStatement(lineNumb);
	 state.setCurrentLine(program.getNextLineNumber(lineNumb));
	 stmt->execute(state);
	 priorLineNumb=lineNumb;
	 lineNumb=state.getCurrentLine();
       }
     }
     else if(token=="CLEAR"){
       program.clear();
     }
     else if(token=="HELP"){
       cout<<"Minimal Basic Statements"<<endl; 
       cout<<"REM   This statement used for comments"<<endl;
       cout<<"LET   This statement is BASIC's assigment statement"<<endl;
       cout<<"PRINT In minimal BASIC, the PRINT statement has the form: "<<endl;
       cout<<"         PRINT exp"<<endl;
       cout<<"      where exp is an expression."<<endl;
       cout<<"INPUT In the minimal version of the BASIC interpreter, the INPUT statement has the form:"<<endl;
       cout<<"         INPUT var"<<endl;
       cout<<"      where var is a variable read in from the user"<<endl;
       cout<<"GOTO  This statement has the syntax"<<endl;
       cout<<"         GOTO n"<<endl;
       cout<<"      which forces the program to continue from line n instead of continuing with the next statement"<<endl;
       cout<<"IF    This statement provides conditional control. The syntax for this statement is: "<<endl;
       cout<<"      IF exp1 op exp2 THEN n"<<endl;
       cout<<"      where exp1 and exp2 are expressions and op is one of the conditional operators =, <, or >."<<endl;
       cout<<"END   This statment marks the end of the program."<<endl;
       cout<<"Commands to control the BASIC interpreter"<<endl;
       cout<<"RUN   This command starts program execution beginning at the lowest-numbered line. "<<endl;
       cout<<"LIST  This command lists the steps in the program in numerical sequence."<<endl;
       cout<<"CLEAR This command deletes the program so the user can start entering a new one."<<endl;
       cout<<"HELP  This command provides a simple help message describing the interpreter."<<endl;
       cout<<"QUIT  Typing QUIT exits from the BASIC interpreter by calling exit(0)."<<endl;	 
     }
     else if(token=="QUIT"){
       exit(0);
     }
     else
       cout<<"Invalid command"<<endl;     
   }
}
Exemplo n.º 20
0
EndStmt::EndStmt(TokenScanner &scanner) {
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}
Exemplo n.º 21
0
/* main() manages the user interface;
 * instantiates priority queue object, then operates loop to read input 
 * from user and call the appropriate priority queue method
 */
int main() {
   PriorityQueue pq;
   TokenScanner scanner;
   while (true) {
      string line = getLine("> ");
      scanner.setInput(line);
      scanner.ignoreWhitespace();
      string cmd=scanner.nextToken();
      if (cmd == "help") {
         helpCommand();
      }      
      else if (cmd == "enqueue") {
	if(scanner.hasMoreTokens()){
	  string value=scanner.nextToken();
	  if(scanner.hasMoreTokens()){
	    scanner.scanNumbers();
	    string priorityStr=scanner.nextToken();
	    double priority=stringToDouble(priorityStr);	
	    pq.enqueue(value,priority);
	  }
	  else
	    pq.enqueue(value);
	}
      }    
      else if (cmd == "dequeue") {
	if(pq.isEmpty())
	  cout<<"The queue is empty"<<endl;
	else
	  cout<<pq.dequeue()<<endl;
      }
      else if (cmd == "peek") {
	if(pq.isEmpty())
	  cout<<"The queue is empty"<<endl;
	else
	  cout<<pq.peek()<<endl;
      }
      else if (cmd == "peekPriority"||cmd=="peekpriority") {
	if(pq.isEmpty())
	  cout<<"The queue is empty"<<endl;
	else
	  cout<<pq.peekPriority()<<endl;
      }
      else if (cmd == "clear") {
	pq.clear();
      }
      else if (cmd == "size") {
	cout<<pq.size()<<endl;
      }
      else if (cmd == "isEmpty"||cmd=="isempty") {
	if(pq.isEmpty())
	  cout<<"true";
	else
	  cout<<"false";
	cout<<endl;
      }
      else if(cmd=="list")
	list(pq);
      else {
         cout << "Undefined command: " << cmd << endl;
      }
   }
   return 0;
}
Exemplo n.º 22
0
/*
 * Implementation notes: the PrintStmt subclass
 * ----------------------------------------------
 * Instances of this class evaluate the expression that is passed
 * to them through the scanner and then print the result using the
 * excecute method.
 */
PrintStmt::PrintStmt(TokenScanner & scanner) {
    exp = readE(scanner, 0);
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}
Exemplo n.º 23
0
GotoStmt::GotoStmt(TokenScanner &scanner) {
    lineNumber = stringToInteger(scanner.nextToken());
    if (scanner.hasMoreTokens()) {
        error("Extraneous token " + scanner.nextToken());
    }
}