public Operation Build(IList <Token> tokens)
{
resultStack.Clear();
operatorStack.Clear();
foreach (Token token in tokens)
{
object value = token.Value;
switch (token.TokenType)
{
case TokenType.Integer:
resultStack.Push(new IntegerConstant((int)token.Value));
break;
case TokenType.FloatingPoint:
resultStack.Push(new FloatingPointConstant((double)token.Value));
break;
case TokenType.Text:
if (EngineUtil.IsFunctionName((string)token.Value))
{
operatorStack.Push(token);
}
else
{
resultStack.Push(new Variable((string)token.Value));
}
break;
case TokenType.LeftBracket:
operatorStack.Push(token);
break;
case TokenType.RightBracket:
PopOperations(true, token);
break;
case TokenType.Operation:
Token operation1Token = token;
char operation1 = (char)operation1Token.Value;
if (operatorStack.Count == 0)
{
operatorStack.Push(operation1Token);
}
else
{
Token operation2Token = operatorStack.Peek();
bool isFunctionOnTopOfStack = operation2Token.TokenType == TokenType.Text;
if (!isFunctionOnTopOfStack)
{
char operation2 = (char)operation2Token.Value;
if ((IsLeftAssociativeOperation(operation1) && operationPrecedence[operation1] <= operationPrecedence[operation2]) ||
(operationPrecedence[operation1] < operationPrecedence[operation2]))
{
operatorStack.Pop();
operatorStack.Push(operation1Token);
resultStack.Push(ConvertOperation(operation2Token));
}
else
{
operatorStack.Push(operation1Token);
}
}
else
{
operatorStack.Pop();
operatorStack.Push(operation1Token);
resultStack.Push(ConvertFunction(operation2Token));
}
}
break;
}
}
PopOperations(false, null);
VerifyResultStack();
return(resultStack.First());
}
