Re: [boost] [Describe] My review of Describe

Andrzej Krzemienski wrote:

pt., 5 mar 2021 o 09:00 Julien Blanc via Boost napisał(a): ...

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It looks that there's a mix of apples and orange in this enum. Some values acts as they will include more data in the results, some on the contrary will filter, and some will change completely the type of the members enumerated. This is not obvious when reading the documentation, and there's just nothing in the name of the enumerated values that will hints the user about what it really does.

This design issue is my main motivation for the conditional acceptance of the library: i think it should not be accepted until this part is fixed.

I agree with the observation. My explanation for it (I do not know the real motivation, just saying as a reviewer) is that it is driven by use cases.

That is correct. I already gave a partial answer in https://lists.boost.org/Archives/boost/2021/03/250949.php, but that may have been too short. The majority of use cases deal with nonstatic data members, so the library makes this the default (you don't need to supply any modifier in order to get the nonstatic data members.) In contrast, there's no good default for accessibility. Some use cases need just the public members, some need public+protected, some need all, some need public+protected and separately the private ones, and so on. The cases where one needs the static members are rarer. And since the type of the pointer returned in the descriptor differs between static and nonstatic, one typically doesn't need both returned at the same time. In the rarer still cases where one does want both static and nonstatic members at the same time, there's always the option of mp_append-ing the two descriptor lists. So the design approach here is to keep the more common cases short, while leaving advanced uses more complex. There are many ways one can redesign the modifiers, and I already went through most of them. This is what I have settled on. I do accept the feedback that this needs better documentation, and perhaps comments in modifiers.hpp for the people who look there first (don't we all).