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Comment by nly | Hacker News Reader

A good article, but what disturbs me is that the author, while obviously aware of relatively good C++ and programming practices, has somehow arrived in a place where he discounts essentially all of C++s core competencies... like claiming RAII is "far from optimal", that exception safety is "a constant mental overhead", and that copy and move semantics involve writing "a lot of code". These are fairly outrageous claims, and it all smells of total burnout, and losing sight of the forest for the trees, to me.

I feel if the author refocused on his C++ basics instead of bemoaning lots of peripheral crap (like OOP, and the unsuitability of the STL for game dev) he'd reconsider some joy in C++ again.

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I think one of the main reasons why he did what he did is his motivation, or lack of it while working with C++. Whatever rational arguments would point out to C++ will be essentially meaningless if he is not happy writing with it. That's why discipline is so important in any work. Motivation can get you just so far. It is highly volatile and unreliable. I think it's safe to assume that the author soon will get tired of C and move to languages like python and write an article of how optimizations aren't that important compared to productivity and how critical parts can be written in C, etc. Great article for his perspective and some pros/cons of C/C++, but take it with a grain of salt.

Absolutely you should take the text with a grain of salt. The reasons I chose C are very personal.

I can entertain the idea that my desire for simplicity is just a fad. I suspect that I wouldn't move to something like Python (I use it for other purposes though), because I don't like optimizing. I want a mindset which helps producing code with reasonable productivity, and of which performance I don't need to worry much. But yeah, it's possible that I'll change my mind and write an article about how I was so wrong before :P

I see unwillingness to adopt the modern and relatively extreme ways to use contemporary C++ well, only the old and simple painful ways to use "C with classes" with serious issues.

For example, the paragraph about loading and saving game state postulates "using the ideas of polymorphism and encapsulation", automatically throwing a lot of pointers and vtables in the way of reading and writing a binary blob like in the C engine. A serious C++ engine with a "data oriented" design would have the same arrays of primitive types and dumb structs as its C counterpart, merely dressed as std::vector or std::array.

> A serious C++ engine with a "data oriented" design would have the same arrays of primitive types and dumb structs as its C counterpart, merely dressed as std::vector or std::array

Yeah, I agree. Including the "full C++" to the comparison was just trying to avoid having to argue about which is the "right" subset of C++ for engines, which is somewhat besides the point. The main problems I have with modern, data-oriented C++ are mostly compile times, slow debug builds and non-trivial reflection.

Some don't mind those, and be happy.

> like claiming RAII is "far from optimal", that exception safety is "a constant mental overhead", and that copy and move semantics involve writing "a lot of code". These are fairly outrageous claims

I agree with the OP on all three counts. I don't think RAII is very nice (python-esque with-statement would be nicer IMO), exception safety is really a mental overhead unless you restrict exceptions to a minimum and the copy-assign-move semantics do add a bit of work to every class you introduce.

These are not outrageous claims, they're rather valid opinions. Feel free to disagree but I'm siding with OP on this one.

Overall I dislike C++'s value based semantics, not because it's inherently bad, but it's just so different to any other (reference based) languages that only a small minority of programmers know how to work with them. Attaching complex semantics to types (overloading, templates) and virtual functions/inheritance (when overused) makes reading code much harder and often you need to resort to stepping in the debugger to find out where a function call actually leads.

Well written C++ can be really nice at best, but unfortunately most C++ code bases out there seem to be either a bastard mix of C, Java and C++ styles or over-the-board boost-ey template mess. Neither of these extremes hits the sweet spot.

> I don't think RAII is very nice (python-esque with-statement would be nicer IMO)

You can implement Pythons 'with' statement in C++ with almost the same syntax and exactly the same terseness. This shouldn't be surprising, since C++'s value-semantic constructor-destructor mechanism is simply more general and fundamental.

> copy-assign-move semantics do add a bit of work to every class you introduce.

Only if you fill your objects with multiple dumb C pointers to other objects ad nauseam. If you embrace value semantics and smart pointers you almost never have to write any of the "rule of 5", and when you do it's straightforward. Simple rule: a class should never contain handles or pointers to more than a single resource. Composition handles the rest.

When I mentioned Python's with statement, that's really all I'd want. Something neater than C's "goto error" error handling, but not much more than that. I think there's constructs like this in some languages.

> Simple rule: a class should never contain handles or pointers to more than a single resource. Composition handles the rest.

The issue with this is that in the real world, you have to deal with 3rd party libraries and frameworks or even the OS syscall interface which don't follow this guideline. So you'll end up writing wrappers for all your "foreign" objects from any other libraries you use. This is a lot of work and creates impedance mismatch problems when there's no simple clearly established concept of ownership (e.g. the wrapped objects are already reference counted) or the assumptions of the library aren't friendly to C++ style semantics.

If you live in a "modern C++ only" bubble, this isn't an issue.

Here's an ugly hacked up version of Pythons 'with' statement:

https://gist.github.com/nlyan/7319c7b2a6328460ce9c

As for external libraries...sometimes it requires a bit of ingenuity to find that perfect 'wrap everything!' vs 'write C' balance... but it's usually not so bad if you approach the problem judiciously. unique_ptr and shared_ptr's capabilities are often underestimated in this regard for instance. Both can be used with external reference counting, the former being the most efficient.

>These are fairly outrageous claims, and it all smells of total burnout, and losing sight of the forest for the trees, to me.

Maybe, I don't know. I have been a lot happier with C though, while still writing some C++ code during the year.

Interesting, since I feel just the opposite. In C++, most of the time, I can write the precise intent of what the code should do, and I can also choose the level of abstractness, without compromising on performance!

I think the main trick with C++ is to learn the best practices first, and only use those one thoroughly understood.

I'm happy when I'm writing C. It's only when I look back on a week of coding and realise how little functionality I implemented that I realise it's a bad idea.

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