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Comment by xtrapolate | Hacker News Reader

You can "test the theory behind ownership semantics" without relying on the intricacies of a C++11 construct (however trivial).

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Unique_ptr is such a fundamental type that, if one claims to be a c++ programmer, one has to know it and understand how it works.

> "Unique_ptr is such a fundamental type that, if one claims to be a c++ programmer, one has to know it and understand how it works."

No.

Those utilities weren't standardized before C++11. People wrote their own implementations before that. People had to understand stack unwinding and scoping, memory, RAII, design patterns that relate to allocation/de-allocation of memory, ownership transfer.

Then came in the people that decided it'd be a great idea to start quizzing others about C++11 concretions.

> Then came in the people that decided it'd be a great idea to start quizzing others about C++11 concretions.

So it has been almost a decade. How much longer before the whole move semantics addition to the language specification becomes relevant to you?

Move semantics are nice, but they aren't critical or even fundamental to understanding C++. I would bet most C++ programmers do not fully understand them.

As a veteran of three decades of C++, I've seen a lot of new hotness turn into old and busted and removed. There's plenty of dark corners where you don't need to look to get a job done.

When the embedded project I've been working on since 2009 decides to upgrade compiler versions (which will be approximately never). Or when I change jobs or move on to a different project.

My workplace is still using c++98 since upgrading compilers was too much work and a compatibility risk for our customers. This year I spend almost a month getting new versions of our dependencies to run with the existing setup, cutting out various features along the way. Avoiding that upgrade is no longer beneficial for us.

> "So it has been almost a decade. How much longer before the whole move semantics addition to the language specification becomes relevant to you?"

I'm not debating the usefulness of move semantics. I'm debating the weight being placed on them in these so-called "C++ interview questions". Wouldn't it be better to discuss the actual problem, rather than a concrete solution we ended up having in C++11?

> Those utilities weren't standardized before C++11.

That's quite a disigenuous statement. Work on C++11 started after the approval of c++98, and the c++0x smart pointers have been implemented and available for quite a while before C++11 was finalized.

I would question where you learned the "theory" behind modern c++ ownership semantics without ever encountering std::unique_ptr, given that it is the reason move semantics were added to the language. As far as I can tell you would have a hard time even finding a source on post c++11 ownership semantics that doesn't mention std::unique_ptr at all. So not knowing about std::unique_ptr seems like a good indication that your sources were c++98 based, making your "theory" a decade out of date.

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