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0 pointsAnimalMuppet5y ago0 comments

I have literally never seen someone program C++ that way. I mean, it's probably true that some people somewhere are doing that. But saying "C++ developers rightfully avoid using its OO functionality as much as possible" seems like a complete distortion of the actual situation.

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Kranar5y ago· 2 in thread

Those some people would be the authors of the standard library who use type erasure for std::function, std::string_view, std::span, std::any, std::ranges, std::fmt, the new class of pmr memory allocators use type erasure, the upcoming coroutines are built on type erasure.

Common C++ libraries like boost have an entire library dedicated to type erasure:

https://www.boost.org/doc/libs/1_75_0/doc/html/boost_typeera...

Facebook's Folly library also provides type erasure functionality:

https://github.com/facebook/folly/blob/master/folly/docs/Pol...

Google's Abseil is full of type erasure:

https://abseil.io/

Here is Adobe's C++ library for type erasure:

https://stlab.adobe.com/group__poly__related.html

And here's a talk by Sean Parent about how Adobe uses type erasure to emulate runtime polymorphism without using C++'s native OO features:

https://www.youtube.com/watch?v=QGcVXgEVMJg

I suppose these are just some people somewhere...

pjmlp5y ago

And all of them use some kind of OOP ideas, while trying to sell themselves as not being OOP.

classes, polymorphism, some level of inheritance, delegation, composition, builders, method dispatch, ....

Kranar5y ago

None of them are selling themselves as not being OOP.

What they are doing is implementing an ad-hoc version of OOP that forgoes using C++'s native OO feature-set. Native C++ OO clashes with modern C++, often creating a dialect that does not play well with resource management and common C++ idioms.

The type erasure libraries provide many of the traditional benefits of OO but allow you to retain value semantics (which native C++ OO does not).

My argument was never about OO as a general concept, it was strictly that C++'s native OO feature set is very poor and modern C++ allows developers to move away from that feature set.

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