/// <summary>
/// Paren() : This method evaluates Parenthesis in the equation and
/// insures they are handled properly according to the Order of Operations. Because this is last in the chain,
/// it also evaluates Variable and Function names.
/// </summary>
/// <returns>CValue object that holds an operation.</returns>
private CValue Paren()
{
bool bFunc = false;
CValue oValue = null;
if (m_currentToken.ToString() == "(")
{
PositionNextToken();
oValue = Relational();
if (m_currentToken.ToString() == ",")
{
return(oValue);
}
if (m_currentToken.ToString() != ")")
{
throw new ApplicationException("Unmatched parenthesis in equation.");
}
}
else
{
switch (m_currentToken.TokenType)
{
case Parser.CharType.CT_NUMBER:
oValue = new CNumber(m_currentToken.ToString());
break;
case Parser.CharType.CT_LETTER:
{
if (m_nextToken.ToString() == "(")
{
int iIdx = m_slFunctions.IndexOfKey(m_currentToken.ToString());
if (iIdx < 0)
{
throw new ApplicationException("Function not found - " + m_currentToken.ToString());
}
CFunction oFunc = (CFunction)m_slFunctions.GetByIndex(iIdx);
ArrayList alValues = new ArrayList();
do
{
PositionNextToken();
oValue = Paren();
alValues.Add(oValue);
} while (m_currentToken.ToString() == ",");
if (m_currentToken.ToString() == ")")
{
PositionNextToken();
}
bFunc = true;
oValue = oFunc.CreateInstance(alValues);
}
else
{
oValue = GetVariableByName(m_currentToken.ToString());
}
break;
}
}
}
if (!bFunc)
{
PositionNextToken();
}
return(oValue);
}