Re: [Quantlib-dev] a simple question

[DU V. DE V. F. G. P. <fra...@ca...>]

>As for QL_NULL_REAL, it doesn't really matter what value is used as =
long as >it's a determined one

Since it is now used as some kind of unitialized value by the quotes =
classes, I would say that it is no longer such an immaterial detail. For =
example if we can encounter the following problem:

	SimpleQuote quote;
	Real value =3D (std::numeric_limits<float>::max)(); //limit case test
	Quote.setValue(value);
	//a few lines of code later ... bug !!!!

>Speaking of which, funny that you came out with a question on Null. =
Just
>yesterday I was thinking of removing it and using boost::optional when =
a
>number might or might not be defined. What do you think?

Maybe you have thought about boost::optional for the same reason. ;-)=20
It would be cleaner indeed. However I'm not convinced that it's a good =
solution yet.
IMO boost::optional a pefect solution in the case of a free function =
which can return invalid result even in normal situations. (like the =
second example of boost optional tutorial).

On the hand it seems to me that using it for a function member would add =
some spurious trickyness to the class. What do you think of this =
implementation ?=20

	Quote():isValid_(false){}

	virtual void resetQuote() {
	    isValid_ =3D false;
	}

	virtual bool isValid() const {
	    return isValid_;
	};
	private:
	bool isValid_;


regards,

Fran=E7ois