[Quantlib-dev] Private versus Protected

[Chuck H. <cah...@ea...>]

My question is whether there is a good reason for private scope in QuantLib=
 classes. I would like QuantLib to have protected scope rather than private=
 so that developers can inherit the local variables and methods in their su=
bclasses.

In my specific example my financial analyst trusts nothing and always wants=
 to see the intimate details of all calculations to validate correct operat=
ion of the classes we use from QuantLib and those classes that we write. We=
 recently wrote a class to calculate the forward volatilities for caps usin=
g the CapFloor and BlackCapFloorEngine classes. Since these classes hide im=
portant parts in private scope I couldn=92t inherit from them and display t=
heir guts, so I copied the CapFloor and BlackCapFloorEngine classes, change=
d private to protected, inherited from the copies, and wrote subclasses wit=
h methods to save and display the caplet/floorlet values at each iteration =
and some other intimate details. Copying QuantLib classes and inheriting fr=
om them makes me feel like I am doing something foolish and shortsighted.

regards, Charles