C++ Weekly - Ep 225 - Understanding Operator Overloading

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[Tyranisaur]

The operator << for ostream is basically the poster child of operators you want to overload.

[LesleyLai]

Just first time realize that the "Hello, ..., on-site training" monologue is probably not prerecorded.

[akj]

11:30 Haha nice.

By the way, this could have been a nice intro to implementing smart pointers or std::integral_constant.

Some further points could include: literal overloading, type overloading and the Return Type Resolver Idiom.

[MartinDE]

This is the first time I'm not convinced of the message of this "primer". It is technically not that difficult to overload operators. But like you, @Jason, explicitly stated … be aware to do the right thing only the right … without telling something about how to do the right decisions in necessary or needed or good operator overloading.
I personally need a guideline about when and why and not technically how!

[warrenbuckley]

Whoa Jason, upping your frame transition game I see

[japedr]

I have a couple of questions:

1 - At 5:58, why is there an implicit conversion depending on the rhs/lhs order?
Is it because of some kind of parsing rules?
If I understand it correctly, the expression:
c+4.5
Gets implicitly converted via constructor call, as if it were
c+Complex{4.5}
So I would expect that
4.5 + c
Gets converted into
Complex{4.5} + c
But it doesn't.

2 - At 6:47, is "static" instead of "friend" possible for operator+? If so, is there a difference?
Also, is there a difference between friend function definition inside class declaration (like in the example) and friend definition outside it (I understand that there has to be a forward declaration anyways)?

Thanks for your videos. They are quite helpful.

[fredhair]

I think the only time I can ever claim to know more C++ than Jason was the ordering of that [[nodiscard]]! 😂 Not much of a brag but it's probably the best I'll ever get. Very interesting video is there any way of making it so the ordering of operator args redundant. Usually the ordering of operator arguments is very important but it would seem that a + generally for many types should be sorta bidirectional. e.g. complexB = complexA + doubleA is not the same as complexB = doubleA + complexA.

[homomorphic]

Who, on the standard committee allowed overloading "/=" for path concatenation in std::filesystem:: path?

[LeoHsieh]

C++ really has bad readibility. [Nodiscard] friend constexpr....

[Clouds]

For the pointer example, which operator overload would be called? The const or non-const one?

[patlecat]

The friend function version looks weird. Should this even be allowed? Isn't the spaceship operator in C++20 not a better option?

[Spartan]

A lot of people get mad at C++'s (and thus blame C++) operator overloading because of people making stupid overloads, which annoys me because the language shouldn't be blamed for people doing stupid things, you can do stupid crap in every language, just because C++ allows you to do a lot of stupid things if you're feeling stupid doesn't mean its the language's fault.

[KennyMinigun]

5:41 this behavior will change in C++20. Funny enough, the code will still not compile, but for a different reason (small `const` will fix that)

[EpicSnakes]

I hope in C++23, operator+ and operator- will be defaulted for struct like this

[ameyabhurke]

There were 5 dislikes for this video at the time of this comment. Why??

[plushsu]

wow, you are really ONE QUICK TYPIST....

[cpubug]

I want to make a AI like Jarvis but I don't know how I love this language