On 2017-03-29 14:11, Marc Mutz wrote: > On 2017-03-29 18:57, Matthew Woehlke wrote: >> I think the main reason some many people disagree with you on CoW and >> related subjects is because you put performance above all else, >> including correctness and ease of use. > > Interesting. My criticism of CoW is about correctness _and_ performance. > I have given the iterator-into-copied-container example several times > now. Correctness issue.
I suspect that's not very common, or more people would complain about it. It's also possible to implement CoW in a way that doesn't have this issue. (I've done it, but I believe it would be impractical or compatibility-breaking to retrofit into Qt containers. Also, it requires some extra bookkeeping that probably doesn't improve performance.) > I have also said that what I hate most about > QList is how the memory layout depends on intricate details like the > machine word size. Correctness issue. Granted, but that isn't related to CoW. I have seen much less disagreement on being consistent whether a container stores the items indirectly. -- Matthew _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development