13 Comments to “Scott Meyers – The evolving search for effective C++ – Keynote @ Meeting C++ 2014”

1. Ludwig Behm

   26 Tháng Ba, 2021 at 4:21 chiều

   Can't find it in the comments so for everyone interested: the map emplace function has to allocate a map Node which contains a T. It is assumed that "normally" you successfully insert with a call to emplace.
   For optimizations Node allocation does 2 things at once: allocate memory for Node and T. As it does the allocation it HAS TO do initialization as well, resulting in a Node which contains a T – both initialized and healthy. After that key comparison and insertion into the container happens as explained in the talk.
   Hope this is understandable.

   Reply
2. Patrick Proctor

   26 Tháng Ba, 2021 at 4:21 chiều

   Why an assignment happens as part of what should be in-place construction within existing space in a container is baffling to me. Sounds like a shortcoming of the library implementation to me. Rust can do this no problem. If the target location already has a T, well, destruct T and construct a fresh T in place. Why is this not standard behavior?

   As for QWUKs, utterly ridiculous. You can easily use reflection to get around this extra allocation & deallocation for God's sake. The arguments come in in constructor order do they not? Writing the assembly to do this for an object is easier than writing the C++ to orchestrate it for all types, but seriously?

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3. wotcherfaz

   26 Tháng Ba, 2021 at 4:21 chiều

   WTF nobody's laughing at the jokes LOL
   However, at least they did ask some good questions at the end.

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4. User Accout

   26 Tháng Ba, 2021 at 4:21 chiều

   The more I read the standard or look up research such as he's pointing out, the more I stop worrying about writing "proper" C++. Such a thing doesn't exist.

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5. Quentin UK

   26 Tháng Ba, 2021 at 4:21 chiều

   Das ist sehr funny.

   Reply
6. Gheorghe Curelet-Balan

   26 Tháng Ba, 2021 at 4:21 chiều

   From "prefer" to "consider" emplacement instead of insertion, ie from min 1910 to 5445 & 5730

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7. Tamás Szelei

   26 Tháng Ba, 2021 at 4:21 chiều

   It's a shame the audience only gets about a quarter of his jokes. He's such a unique person in tech, sad to see him retire from C++.

   Reply
8. Joshua Briefman

   26 Tháng Ba, 2021 at 4:21 chiều

   Very useful, Thanks! 🙂

   Reply
9. Ariel Gabizon

   26 Tháng Ba, 2021 at 4:21 chiều

   How come VC++ implementation requires so much more commands at times?

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10. Al-Shaif Hirboush

    26 Tháng Ba, 2021 at 4:21 chiều

    while these guys spent 2 hours analyzing all the inane implications of specific c++ standard library API implementations and everything going on under the hood, people were getting actual work done in C.

    Reply
11. petas874

    26 Tháng Ba, 2021 at 4:21 chiều

    It's really annoying how low the output volume is. Listening to music before and after can be dangerous, when you forget that you've increased the volume tenfolds only to listen to this video.

    Reply
12. Penny Lane

    26 Tháng Ba, 2021 at 4:21 chiều

    Scott was surprisingly pissed about "You should make an item about that." 😉

    Reply
13. von nobody

    26 Tháng Ba, 2021 at 4:21 chiều

    Isn't Scott wrong about "direct init" and "copy init" in `push_back` and `emplace_back` cases? `push_back` need convert arg to T before calling function that can't use explicit constructors. `emplace_back` send arg to constructor directly that is explicit call with `nullptr`.

    Reply