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Don’t blindly prefer emplace_back to push_back

(quuxplusone.github.io)
178 points todsacerdoti | 2 comments | 04 Mar 21 08:02 UTC | HN request time: 0.473s | source
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jokoon ◴[04 Mar 21 10:40 UTC] No.26340841[source]▶
Thanks for the article, there should be a huge list of those type of classic C++ misconceptions/FAQ style.

One of my favorite is "you don't need a linked list".

Although I'm still genuinely interested when a linked list is best suited. I'm also curious why they were invented and why they're taught, maybe just for teaching purposes...

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1. 4fips ◴[04 Mar 21 11:21 UTC] No.26341086[source]▶
Linked lists become really powerful and performant when implemented as intrusive containers, such containers do not need to live on heap and can be embedded directly into another data structures, so an element can be linked into multiple containers at the same time, this gives great flexibility and compactness (especially when indices are used to form the links instead of pointers).
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2. eru ◴[04 Mar 21 13:06 UTC] No.26341829[source]▶
Similarly, some data structure and algorithmic choices that don't make much sense when operating in RAM, can suddenly become appropriate in different environments.

Eg when working on hard disks (eg think a file system or database with raw storage access). Or if you are working in a medium were you can only write once, and can't change what's already written, etc.