internal void ApplyToken(ExpressionToken token)
{
if (token.IsRightParen && _lastWasFunction)
{
_functionStack.Peek().NumTerms = 0;
}
_lastWasFunction = false;
if (token.IsFunction)
{
_functionStack.Push(token);
_lastWasFunction = true;
token.NumTerms = 1;
}
if (token.IsLeftParen)
{
if (!_lastWasOperator)
{
ExpressionToken callToken = new FunctionCallToken(token.Text, _functionEvaluator, token.TokenPosition);
ApplyToken(callToken);
}
_operatorStack.Push(token);
_lastWasOperator = true;
return;
}
if (token.IsTerm)
{
_tokenQueue.Enqueue(token);
_lastWasOperator = false;
return;
}
if (token.IsArgumentSeparator)
{
while (_operatorStack.Count > 0 && !_operatorStack.Peek().IsLeftParen)
{
_tokenQueue.Enqueue(_operatorStack.Pop());
}
_functionStack.Peek().NumTerms++;
_lastWasOperator = true;
return;
}
if (token.IsRightParen)
{
while (_operatorStack.Count > 0)
{
ExpressionToken stackOperator = _operatorStack.Pop();
if (stackOperator.IsLeftParen)
{
if (_operatorStack.Count > 0 && _operatorStack.Peek().IsFunction)
{
_tokenQueue.Enqueue(_operatorStack.Pop());
_functionStack.Pop();
}
break;
}
_tokenQueue.Enqueue(stackOperator);
}
_lastWasOperator = false;
return;
}
if (_lastWasOperator != token.IsUnary)
{
if (token.Alternate != null)
{
ApplyToken(token.Alternate);
return;
}
throw new LexerException("Misplaced operator " + token.Text, token.TokenPosition, token.Text);
}
// When we get here, it certainly is an operator or function call
while (_operatorStack.Count > 0)
{
ExpressionToken stackOperator = _operatorStack.Peek();
if ((token.Associativity == OperatorAssociativity.Right && token.Precedence < stackOperator.Precedence) ||
(token.Associativity == OperatorAssociativity.Left && token.Precedence <= stackOperator.Precedence))
{
_tokenQueue.Enqueue(_operatorStack.Pop());
}
else
{
break;
}
}
_operatorStack.Push(token);
_lastWasOperator = true;
}