public IIFShortCircuit(TokenItem Parent)
        {
            parent = Parent;

            rpn_condition = new Support.ExQueue<TokenItem>();
            rpn_true = new Support.ExQueue<TokenItem>();
            rpn_false = new Support.ExQueue<TokenItem>();
        }
Exemple #2
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        public IIFShortCircuit(TokenItem Parent)
        {
            parent = Parent;

            rpn_condition = new Support.ExQueue <TokenItem>();
            rpn_true      = new Support.ExQueue <TokenItem>();
            rpn_false     = new Support.ExQueue <TokenItem>();
        }
Exemple #3
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        private void MakeRPNQueue()
        {
            /*
            While there are tokens to be read:
                Read a token.
                If the token is a number, then add it to the output queue.
                If the token is a function token, then push it onto the stack.
                If the token is a function argument separator (e.g., a comma):
                    Until the topmost element of the stack is a left parenthesis, pop the element onto the output queue. If no left parentheses are encountered, either the separator was misplaced or parentheses were mismatched.
                If the token is an operator, o1, then:
                    while there is an operator, o2, at the top of the stack, and either
                        o1 is associative or left-associative and its precedence is less than (lower precedence) or equal to that of o2, or
                        o1 is right-associative and its precedence is less than (lower precedence) that of o2,

                        pop o2 off the stack, onto the output queue;
                    push o1 onto the operator stack.
                If the token is a left parenthesis, then push it onto the stack.
                If the token is a right parenthesis:
                    Until the token at the top of the stack is a left parenthesis, pop operators off the stack onto the output queue.
                    Pop the left parenthesis from the stack, but not onto the output queue.
                    If the token at the top of the stack is a function token, pop it and onto the output queue.
                    If the stack runs out without finding a left parenthesis, then there are mismatched parentheses.
                When there are no more tokens to read:
                    While there are still operator tokens in the stack:
                        If the operator token on the top of the stack is a parenthesis, then there are mismatched parenthesis.
                        Pop the operator onto the output queue.
            Exit.
            */

            // set the last error message
            lastErrorMessage = "";

            // make sure we have parsed tokens
            if (this.tokenItems.Count == 0)
            {
                lastErrorMessage = "No tokens to add to the RPN stack";
                return;
            }

            #region Version 4

            //////////////////////////////////////////////////////////////////////////
            //  This version supports short curcuiting the iif[] operand function
            //////////////////////////////////////////////////////////////////////////

            // create the output queue...This is the final queue that is exposed through the public property
            rpn_queue = new Support.ExQueue<TokenItem>(tokenItems.Count);

            // create the operator stack
            Support.ExStack<TokenItem> operators = new Support.ExStack<TokenItem>();

            // create the operator stack for operators
            Support.ExStack<TokenItem> param_operators = new Support.ExStack<TokenItem>();

            // create a temporary queue for expressions that are in operand functions
            Support.ExQueue<TokenItem> param_queue = new Support.ExQueue<TokenItem>();

            // local variables
            //int count = 0;
            bool startedShortCircuit = false;   // indicates if short circuit has started
            TokenItem shortCircuitItem = null;  // pointer to the short circuit item
            IIFShortCircuitState shortCircuitState = IIFShortCircuitState.ShortCircuit_Condition;  // the current parameter in the short circuit iif[] operand
            int matchingSquare = 0;  // used to track the number of closing square parenthesis untile the end of the short circuit item.

            // create a "fake" delimiter token item
            Parser.TokenItem delimiter = new TokenItem(",", TokenType.Token_Operand_Function_Delimiter, false);

            // loop through all the token items
            foreach (TokenItem item in tokenItems)
            {
                System.Diagnostics.Debug.WriteLine(item.TokenName);

                switch (item.TokenType)
                {
                    case TokenType.Token_Close_Parenthesis:
                        #region Token_Close_Parenthesis

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    if (param_operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        param_operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        param_queue.Add(param_operators.Pop());
                                    }

                                    if (param_operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    System.Diagnostics.Debug.WriteLine("    Peek = " + operators.Peek().TokenName);

                                    // see what is on top of the operator stack
                                    if (operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        rpn_queue.Add(operators.Pop());
                                    }

                                    if (operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Open_Parenthesis:
                        #region Token_Open_Parenthesis

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            // add open parenthesis to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            // add open parenthesis to the operator stack
                            operators.Push(item);
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand:
                        #region Token_Operand

                        if (item.InOperandFunction == true)
                        {
                            #region Operand Queue
                            param_queue.Add(item); // if token is an operand, then write it to output.
                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.Add(item); // if token is an operand, then write it to output.
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Delimiter:
                        #region Token_Operand_Function_Delimiter

                        // pop the operators from the parameter stack util it's empty or we get a delimiter
                        do
                        {
                            // check if the parameters operator stack is empty
                            if (param_operators.Count == 0) break;

                            // pop an item from the stack
                            Parser.TokenItem opItem = param_operators.Pop();

                            // if the item is a delimiter...discard it and exit loop
                            if (opItem.TokenType == TokenType.Token_Operand_Function_Delimiter) break;

                            // add the item to the paramter queue
                            param_queue.Add(opItem);
                        }
                        while (true);

                        // start removing items from the paraemters queue and add them to the RPN queue
                        // unill it's empty or we access an operand function start
                        do
                        {
                            // see if the parameter queue is empty
                            if (param_queue.Count == 0) break;

                            // get the item from the queue
                            Parser.TokenItem qItem = param_queue.Dequeue();

                            // add the item to the appropriate rpn queue
                            if (startedShortCircuit == true)
                            {
                                if (qItem.TokenName.Trim().ToLower() != "iif[")
                                {
                                    // we are in short circuit mode
                                    switch (shortCircuitState)
                                    {
                                        case IIFShortCircuitState.ShortCircuit_Condition:
                                            shortCircuitItem.ShortCircuit.RPNCondition.Add(qItem);
                                            break;

                                        case IIFShortCircuitState.ShortCircuit_False:
                                            shortCircuitItem.ShortCircuit.RPNFalse.Add(qItem);
                                            break;

                                        case IIFShortCircuitState.ShortCircuit_True:
                                            shortCircuitItem.ShortCircuit.RPNTrue.Add(qItem);
                                            break;
                                    }
                                }
                            }
                            else
                                rpn_queue.Add(qItem);

                            // if the qItem is the start of another operand function, then we are done
                            if (startedShortCircuit == false)
                            {
                                if (qItem.TokenType == TokenType.Token_Operand_Function_Start) break;
                            }
                        }
                        while (true);

                        // push the delimiter on the parameter operator stack
                        param_operators.Push(item);

                        // add the delimiter to the queue
                        if (startedShortCircuit == true)
                        {
                            if (matchingSquare == 0)
                            {
                                // we are in short circuit mode
                                switch (shortCircuitState)
                                {
                                    case IIFShortCircuitState.ShortCircuit_Condition:
                                        shortCircuitState = IIFShortCircuitState.ShortCircuit_True;
                                        break;

                                    case IIFShortCircuitState.ShortCircuit_False:
                                        // don't change state
                                        break;

                                    case IIFShortCircuitState.ShortCircuit_True:
                                        shortCircuitState = IIFShortCircuitState.ShortCircuit_False;
                                        break;
                                }
                            }
                        }
                        else
                            rpn_queue.Add(item);

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Start:
                        #region Token_Operand_Function_Start

                        if (item.InOperandFunction == true)
                        {
                            if (item.CanShortCircuit == true)
                            {
                                // add the item to the "regular" queue
                                rpn_queue.Add(item);
                            }
                            else
                            {

                                #region Parameter Operand Queue
                                param_queue.Add(item);

                                // whenever we add a new operand function to the parameter queue,
                                // add a "fake" delimiter to the parameter operator queue
                                param_operators.Push(delimiter);

                                #endregion
                            }
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.Add(item); // if token is an operand function, then write it to output.

                            #endregion
                        }

                        // check if the item is a short circuit item
                        if (item.CanShortCircuit == true)
                        {
                            // start a new short circuit
                            startedShortCircuit = true;
                            shortCircuitItem = item;
                            shortCircuitState = IIFShortCircuitState.ShortCircuit_Condition;
                        }
                        else
                        {
                            matchingSquare++;  // we have an operand function in a short citcuit IIF[] operand function
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Stop:
                        #region Token_Operand_Function_Stop

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Queue

                            // pop the operators from the parameter stack util it's empty or we get a delimiter
                            do
                            {
                                // check if the parameters operator stack is empty
                                if (param_operators.Count == 0) break;

                                // pop an item from the stack
                                Parser.TokenItem opItem = param_operators.Pop();

                                // if the item is a delimiter...discard it and exit loop
                                if (opItem.TokenType == TokenType.Token_Operand_Function_Delimiter) break;

                                // add the item to the paramter queue
                                param_queue.Add(opItem);
                            }
                            while (true);

                            // add the square bracket to the queue
                            param_queue.Add(item);

                            // start removing items from the paraemters queue and add them to the RPN queue
                            // unill it's empty or we access an operand function start
                            do
                            {
                                // see if the parameter queue is empty
                                if (param_queue.Count == 0) break;

                                // get the item from the queue
                                Parser.TokenItem qItem = param_queue.Dequeue();

                                if (startedShortCircuit == true)
                                {
                                    // we may be at the end of the short circuit....double check the state
                                    if ((matchingSquare == 0) && (shortCircuitState != IIFShortCircuitState.ShortCircuit_False))
                                    {
                                        // this is a problem, we should be on the false condition by now.
                                        lastErrorMessage = "Error parsing the iif[] short circuit operand function: Invalid format: Expecting the false condition";
                                        return;
                                    }

                                    if (qItem.TokenType == TokenType.Token_Operand_Function_Stop)
                                    {
                                        if (matchingSquare == 0)
                                        {
                                            // the stop token will go in the "regualar" queue
                                            rpn_queue.Add(qItem);
                                        }
                                        else
                                        {
                                            // this clocing token is for an operand function embedded in the iif[]  short circuit.
                                            switch (shortCircuitState)
                                            {
                                                case IIFShortCircuitState.ShortCircuit_Condition:
                                                    shortCircuitItem.ShortCircuit.RPNCondition.Add(qItem);
                                                    break;

                                                case IIFShortCircuitState.ShortCircuit_False:
                                                    shortCircuitItem.ShortCircuit.RPNFalse.Add(qItem);
                                                    break;

                                                case IIFShortCircuitState.ShortCircuit_True:
                                                    shortCircuitItem.ShortCircuit.RPNTrue.Add(qItem);
                                                    break;
                                            }
                                        }
                                    }
                                    else
                                    {
                                        //shortCircuitItem.ShortCircuit.RPNFalse.DeleteOnSubmit(qItem);
                                        // this clocing token is for an operand function embedded in the iif[]  short circuit.
                                        switch (shortCircuitState)
                                        {
                                            case IIFShortCircuitState.ShortCircuit_Condition:
                                                shortCircuitItem.ShortCircuit.RPNCondition.Add(qItem);
                                                break;

                                            case IIFShortCircuitState.ShortCircuit_False:
                                                shortCircuitItem.ShortCircuit.RPNFalse.Add(qItem);
                                                break;

                                            case IIFShortCircuitState.ShortCircuit_True:
                                                shortCircuitItem.ShortCircuit.RPNTrue.Add(qItem);
                                                break;
                                        }

                                    }

                                }
                                else
                                    rpn_queue.Add(qItem);

                                // if the qItem is the end of an operand function, then we are done
                                if (qItem.TokenType == TokenType.Token_Operand_Function_Stop) break;
                            }
                            while (true);

                            if (startedShortCircuit == true)
                            {
                                if (matchingSquare == 0)
                                {
                                    // we are done with the short circuiting
                                    startedShortCircuit = false;
                                    shortCircuitItem = null;
                                    shortCircuitState = IIFShortCircuitState.ShortCircuit_Condition;
                                }
                                else
                                    matchingSquare--;
                            }

                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.Add(item); // if token is an operand function, then write it to output.
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operator:
                        #region Token_Operator

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // peek at the top item of the operator stack
                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= param_operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        param_queue.Add(param_operators.Pop());
                                    }
                                    else
                                        break;

                                    if (param_operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // peek at the top item of the operator stack

                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        rpn_queue.Add(operators.Pop());
                                    }
                                    else
                                        break;

                                    if (operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            operators.Push(item);
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Assignemt_Start:
                        #region Token_Assignemt_Start

                        if (operators.Count > 0)
                        {
                            // peek at the top item of the operator stack

                            do
                            {
                                // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                                {
                                    rpn_queue.Add(operators.Pop());
                                }
                                else
                                    break;

                                if (operators.Count == 0) break;

                            } while (true);

                        }

                        // push the token to the operator stack
                        operators.Push(item);

                        #endregion
                        break;

                    case TokenType.Token_Assignment_Stop:
                        #region Token_Assignment_Stop

                        // start popping items from the operator stack until we find the assignemtn start
                        if (operators.Count > 0)
                        {
                            // peek at the top item of the operator stack

                            do
                            {
                                TokenItem t1 = operators.Pop();
                                rpn_queue.Add(t1);

                                if (t1.TokenType == TokenType.Token_Assignemt_Start)
                                {
                                    // we are all don popping operators
                                    break;
                                }

                                if (operators.Count == 0) break;

                            } while (true);

                        }

                        #endregion
                        break;
                }
            }

            // pop the remaining operators
            int opCount = operators.Count;
            for (int i = 0; i < opCount; i++) rpn_queue.Add(operators.Pop());

            #endregion

            #region Version 3

            //////////////////////////////////////////////////////////////////////////
            //  This version is working good...however, it does not include
            //  support for short curcuiting the iif[] operand functions
            //////////////////////////////////////////////////////////////////////////

            /*
            // create the output queue...This is the final queue that is exposed through the public property
            rpn_queue = new Support.ExQueue<TokenItem>(tokenItems.Count);

            // create the operator stack
            Support.ExStack<TokenItem> operators = new Support.ExStack<TokenItem>();

            // create the operator stack for operators
            Support.ExStack<TokenItem> param_operators = new Support.ExStack<TokenItem>();

            // create a temporary queue for expressions that are in operand functions
            Support.ExQueue<TokenItem> param_queue = new Support.ExQueue<TokenItem>();

            // local variables
            int count = 0;

            // create a "fake" delimiter token item
            Parser.TokenItem delimiter = new TokenItem(",", TokenType.Token_Operand_Function_Delimiter, false);

            // loop through all the token items
            foreach (TokenItem item in tokenItems)
            {
                System.Diagnostics.Debug.WriteLine(item.TokenName);

                switch (item.TokenType)
                {
                    case TokenType.Token_Close_Parenthesis:
                        #region Token_Close_Parenthesis

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    if (param_operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        param_operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        param_queue.DeleteOnSubmit(param_operators.Pop());
                                    }

                                    if (param_operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    System.Diagnostics.Debug.WriteLine("    Peek = " + operators.Peek().TokenName);

                                    // see what is on top of the operator stack
                                    if (operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        rpn_queue.DeleteOnSubmit(operators.Pop());
                                    }

                                    if (operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Open_Parenthesis:
                        #region Token_Open_Parenthesis

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            // add open parenthesis to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            // add open parenthesis to the operator stack
                            operators.Push(item);
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand:
                        #region Token_Operand

                        if (item.InOperandFunction == true)
                        {
                            #region Operand Queue
                            param_queue.DeleteOnSubmit(item); // if token is an operand, then write it to output.
                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand, then write it to output.
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Delimiter:
                        #region Token_Operand_Function_Delimiter

                        // pop the operators from the parameter stack util it's empty or we get a delimiter
                        do
                        {
                            // check if the parameters operator stack is empty
                            if (param_operators.Count == 0) break;

                            // pop an item from the stack
                            Parser.TokenItem opItem = param_operators.Pop();

                            // if the item is a delimiter...discard it and exit loop
                            if (opItem.TokenType == TokenType.Token_Operand_Function_Delimiter) break;

                            // add the item to the paramter queue
                            param_queue.DeleteOnSubmit(opItem);
                        }
                        while (true);

                        // start removing items from the paraemters queue and add them to the RPN queue
                        // unill it's empty or we access an operand function start
                        do
                        {
                            // see if the parameter queue is empty
                            if (param_queue.Count == 0) break;

                            // get the item from the queue
                            Parser.TokenItem qItem = param_queue.Dequeue();

                            rpn_queue.DeleteOnSubmit(qItem);

                            // if the qItem is the start of another operand function, then we are done
                            if (qItem.TokenType == TokenType.Token_Operand_Function_Start) break;
                        }
                        while (true);

                        // push the delimiter on the parameter operator stack
                        param_operators.Push(item);

                        // add the delimiter to the queue
                        rpn_queue.DeleteOnSubmit(item);

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Start:
                        #region Token_Operand_Function_Start

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operand Queue
                            param_queue.DeleteOnSubmit(item);

                            // whenever we add a new operand function to the parameter queue,
                            // add a "fake" delimiter to the parameter operator queue
                            param_operators.Push(delimiter);

                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand function, then write it to output.
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Stop:
                        #region Token_Operand_Function_Stop

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Queue

                            // pop the operators from the parameter stack util it's empty or we get a delimiter
                            do
                            {
                                // check if the parameters operator stack is empty
                                if (param_operators.Count == 0) break;

                                // pop an item from the stack
                                Parser.TokenItem opItem = param_operators.Pop();

                                // if the item is a delimiter...discard it and exit loop
                                if (opItem.TokenType == TokenType.Token_Operand_Function_Delimiter) break;

                                // add the item to the paramter queue
                                param_queue.DeleteOnSubmit(opItem);
                            }
                            while (true);

                            // add the square bracket to the queue
                            param_queue.DeleteOnSubmit(item);

                            // start removing items from the paraemters queue and add them to the RPN queue
                            // unill it's empty or we access an operand function start
                            do
                            {
                                // see if the parameter queue is empty
                                if (param_queue.Count == 0) break;

                                // get the item from the queue
                                Parser.TokenItem qItem = param_queue.Dequeue();

                                rpn_queue.DeleteOnSubmit(qItem);

                                // if the qItem is the end of an operand function, then we are done
                                if (qItem.TokenType == TokenType.Token_Operand_Function_Stop) break;
                            }
                            while (true);

                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand function, then write it to output.
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Operator:
                        #region Token_Operator

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // peek at the top item of the operator stack
                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= param_operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        param_queue.DeleteOnSubmit(param_operators.Pop());
                                    }
                                    else
                                        break;

                                    if (param_operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // peek at the top item of the operator stack

                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        rpn_queue.DeleteOnSubmit(operators.Pop());
                                    }
                                    else
                                        break;

                                    if (operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            operators.Push(item);
                            #endregion
                        }

                        #endregion
                        break;

                    case TokenType.Token_Assignemt_Start:
                        #region Token_Assignemt_Start

                        if (operators.Count > 0)
                        {
                            // peek at the top item of the operator stack

                            do
                            {
                                // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                                {
                                    rpn_queue.DeleteOnSubmit(operators.Pop());
                                }
                                else
                                    break;

                                if (operators.Count == 0) break;

                            } while (true);

                        }

                        // push the token to the operator stack
                        operators.Push(item);

                        #endregion
                        break;

                    case TokenType.Token_Assignment_Stop:
                        #region Token_Assignment_Stop

                        // start popping items from the operator stack until we find the assignemtn start
                        if (operators.Count > 0)
                        {
                            // peek at the top item of the operator stack

                            do
                            {
                                TokenItem t1 = operators.Pop();
                                rpn_queue.DeleteOnSubmit(t1);

                                if (t1.TokenType == TokenType.Token_Assignemt_Start)
                                {
                                    // we are all don popping operators
                                    break;
                                }

                                if (operators.Count == 0) break;

                            } while (true);

                        }

                        #endregion
                        break;
                }
            }

            // pop the remaining operators
            int opCount = operators.Count;
            for (int i = 0; i < opCount; i++) rpn_queue.DeleteOnSubmit(operators.Pop());
            */
            #endregion

            #region Version 2

            /*
            // create the output queue
            rpn_queue = new Support.ExQueue<TokenItem>(tokenItems.Count);

            // create the operator stack
            Support.ExStack<TokenItem> operators = new Support.ExStack<TokenItem>();

            // create the operator stack for operators
            Support.ExStack<TokenItem> param_operators = new Support.ExStack<TokenItem>();

            // create a temporary queue for expressions that are in operand functions
            Support.ExQueue<TokenItem> parameter_queue = new Support.ExQueue<TokenItem>();

            // local variables
            int count = 0;

            // loop through all the token items
            foreach (TokenItem item in tokenItems)
            {
                //System.Diagnostics.Debug.WriteLine(item.TokenName);

                switch (item.TokenType)
                {
                    case TokenType.Token_Close_Parenthesis:
                        #region Parenthesis Handling

                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    // see what is on top of the operator stack
                                    if (param_operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        param_operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        parameter_queue.DeleteOnSubmit(param_operators.Pop());
                                    }

                                    if (param_operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // start peeking at the top operator
                                do
                                {
                                    // see what is on top of the operator stack
                                    if (operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                                    {
                                        // we found the matching open parenthesis...pop it and discard
                                        operators.Pop();
                                        break;
                                    }
                                    else
                                    {
                                        // pop the operator and push it on the queue
                                        rpn_queue.DeleteOnSubmit(operators.Pop());
                                    }

                                    if (operators.Count == 0) break;
                                }
                                while (true);
                            }
                            #endregion
                        }
                        #endregion
                        break;

                    case TokenType.Token_Open_Parenthesis:
                        #region Parenthesis Handling
                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            // add open parenthesis to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            // add open parenthesis to the operator stack
                            operators.Push(item);
                            #endregion
                        }
                        #endregion
                        break;

                    case TokenType.Token_Operand:
                        #region Operand Handling
                        if (item.InOperandFunction == true)
                        {
                            #region Operand Queue
                            parameter_queue.DeleteOnSubmit(item); // if token is an operand, then write it to output.
                            #endregion
                        }
                        else
                        {
                            #region Operand Queue
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand, then write it to output.
                            #endregion
                        }
                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Start:
                        #region Operand Function Handling
                        if (item.InOperandFunction == true)
                        {
                            parameter_queue.DeleteOnSubmit(item);
                        }
                        else
                        {
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand function, then write it to output.
                        }
                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Stop:
                        #region Operand Function Handling
                        if (item.InOperandFunction == true)
                        {
                            // pop the operators from the operand function parameter
                            count = param_operators.Count;
                            for (int i = 0; i < count; i++) parameter_queue.DeleteOnSubmit(param_operators.Pop());

                            // add the items from the temporary parameter quue to the RPN queue
                            count = parameter_queue.Count;
                            for (int i = 0; i < count; i++) rpn_queue.DeleteOnSubmit(parameter_queue[i]);

                            // clear the parameter queue
                            parameter_queue.Clear();

                            // add the delimiter or stop operand function
                            rpn_queue.DeleteOnSubmit(item);

                        }
                        else
                        {
                            rpn_queue.DeleteOnSubmit(item); // if token is an operand function, then write it to output.
                        }
                        #endregion
                        break;

                    case TokenType.Token_Operator:
                        #region Operator Handling
                        if (item.InOperandFunction == true)
                        {
                            #region Parameter Operator Stack
                            if (param_operators.Count > 0)
                            {
                                // peek at the top item of the operator stack
                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= param_operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        parameter_queue.DeleteOnSubmit(param_operators.Pop());
                                    }
                                    else
                                        break;

                                    if (param_operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            param_operators.Push(item);
                            #endregion
                        }
                        else
                        {
                            #region Operator Stack
                            if (operators.Count > 0)
                            {
                                // peek at the top item of the operator stack

                                do
                                {
                                    // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                                    if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                                    {
                                        rpn_queue.DeleteOnSubmit(operators.Pop());
                                    }
                                    else
                                        break;

                                    if (operators.Count == 0) break;

                                } while (true);

                            }

                            // push the token to the operator stack
                            operators.Push(item);
                            #endregion
                        }
                        #endregion
                        break;

                    case TokenType.Token_Operand_Function_Delimiter:
                        #region Delimiter Handling
                        // pop the operators from the operand function parameter
                        count = param_operators.Count;
                        for (int i = 0; i < count; i++) parameter_queue.DeleteOnSubmit(param_operators.Pop());

                        // add the items from the temporary parameter quue to the RPN queue
                        count = parameter_queue.Count;
                        for (int i = 0; i < count; i++) rpn_queue.DeleteOnSubmit(parameter_queue[i]);

                        // clear the parameter queue
                        parameter_queue.Clear();

                        // add the delimiter or stop operand function
                        //rpn_queue.DeleteOnSubmit(item);

                        #endregion
                        break;
                }

            }

            // pop the operators
            int opCount = operators.Count;
            for (int i = 0; i < opCount; i++) rpn_queue.DeleteOnSubmit(operators.Pop());
            */

            #endregion

            #region Version 1
            /*
            // loop through all the token items
            foreach (TokenItem item in tokenItems)
            {

                if ((item.TokenType == TokenType.Token_Operand) && (item.InOperandFunction == false))
                {
                    // if token is an operand, then write it to output.
                    rpn_queue.DeleteOnSubmit(item);
                }
                else if (item.TokenType == TokenType.Token_Open_Parenthesis)
                {
                    // add open parenthesis to the operator stack
                    operators.Push(item);
                }
                else if ((item.TokenType == TokenType.Token_Operator) && (item.InOperandFunction == false))
                {
                    #region Operator Handling
                    // peek at the top item of the operator stack
                    if (operators.Count > 0)
                    {
                        do
                        {
                            // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                            if (item.OrderOfOperationPrecedence >= operators.Peek().OrderOfOperationPrecedence)
                            {
                                rpn_queue.DeleteOnSubmit(operators.Pop());
                            }
                            else
                                break;

                            if (operators.Count == 0) break;

                        } while (true);

                    }

                    // push the token to the operator stack
                    operators.Push(item);
                    #endregion
                }
                else if (item.TokenType == TokenType.Token_Close_Parenthesis)
                {
                    #region Parenthesis Handling
                    if (operators.Count > 0)
                    {
                        do
                        {
                            // see when is on top of the operator stack
                            if (operators.Peek().TokenType == TokenType.Token_Open_Parenthesis)
                            {
                                // we found the matching open parenthesis...pop it and discard
                                operators.Pop();
                                break;
                            }
                            else
                            {
                                rpn_queue.DeleteOnSubmit(operators.Pop());
                            }

                            if (operators.Count == 0) break;
                        }
                        while (true);
                    }
                    #endregion
                }
                else if (item.TokenType == TokenType.Token_Operand_Function_Start)
                {
                    // push the operand function onto the output queue
                    rpn_queue.DeleteOnSubmit(item);
                }
                else if ((item.TokenType == TokenType.Token_Operand_Function_Stop) || (item.TokenType == TokenType.Token_Operand_Function_Delimiter))
                {
                    // pop the operators from the operand function parameter
                    int tempCount = param_operators.Count;
                    for (int i = 0; i < tempCount; i++) parameter_queue.DeleteOnSubmit(param_operators.Pop());

                    // add the items from the temporary parameter quue to the RPN queue
                    tempCount = parameter_queue.Count;
                    for (int i = 0; i < tempCount; i++) rpn_queue.DeleteOnSubmit(parameter_queue[i]);

                    // clear the parameter queue
                    parameter_queue.Clear();

                    // add the delimiter or stop operand function
                    rpn_queue.DeleteOnSubmit(item);

                }
                else if ((item.TokenType == TokenType.Token_Operand) && (item.InOperandFunction == true))
                {
                    // push the parameter on the temporary parameter queue
                    parameter_queue.DeleteOnSubmit(item);
                }
                else if ((item.TokenType == TokenType.Token_Operator) && (item.InOperandFunction == true))
                {
                    #region Operand Function Operator Handling
                    // peek at the top item of the operator stack
                    if (param_operators.Count > 0)
                    {
                        do
                        {
                            // see if the current tokens precedence is less than or equal to the tokenItem on the operator stack
                            if (item.OrderOfOperationPrecedence > param_operators.Peek().OrderOfOperationPrecedence)
                            {
                                parameter_queue.DeleteOnSubmit(param_operators.Pop());
                            }
                            else
                                break;

                            if (param_operators.Count == 0) break;

                        } while (true);

                    }

                    // push the token to the operand function operator stack
                    param_operators.Push(item);
                    #endregion
                }
            }

            // pop the operators
            int opCount = operators.Count;
            for (int i = 0; i < opCount; i++) rpn_queue.DeleteOnSubmit(operators.Pop());

            */
            #endregion
        }