private void ParseDigit()
{
StringBuilder tmpNumber = new StringBuilder();
while (Token.IsDigit(token))
{
CollectToken(ref tmpNumber);
}
operands.Push(double.Parse(tmpNumber.ToString(), System.Globalization.CultureInfo.InvariantCulture));
TryInsertMultiply();
TryRightSideOperator();
}
/// <summary>
/// Parse primary tokens: digits, variables, functions, parentheses
/// </summary>
private void ParsePrimary()
{
if (Token.IsDigit(token)) // reading numbers
{
ParseDigit();
}
else if (Token.IsName(token)) // variable or function (both binary and unary)
{
ParseName();
}
else if (Token.IsUnary(token)) // unary operator (unary minus)
{
PushOperator(Token.ConvertOperator(token));
NextToken();
ParsePrimary();
}
else if (token == Token.PLeft) // parentheses
{
NextToken();
operators.Push(Token.Sentinel); // add sentinel to operators stack
ParseBinary();
Expect(Token.PRight, Token.Separator);
operators.Pop(); // pop sentinel from the stack
TryInsertMultiply();
TryRightSideOperator();
}
else if (token == Token.Separator) // arguments separator in funtions (',')
{
NextToken();
ParsePrimary();
}
else
{
ThrowException("Syntax error");
}
}