[Interest] Small survey on necessary Qt Container size

Ulf Hermann ulf.hermann at qt.io
Tue Sep 27 15:17:00 CEST 2022

I think Andre's point is that you should not use Qt containers for such 
large amounts of data, but rather some other data structure better 
suited for your case (most trivially, std::vector instead of QList).

The implicit sharing of Qt containers is a nice trait that enables you 
to write more concise code as long as it's feasible to copy the data 
when needed. If that is not feasible (i.e. billions of elements), the 
equally implicit detach on write will come back to bite you.

However, I guess there are a lot of people who consciously or 
unconsciously ignore this particular bit of advice and "just" never copy 
a large container unless all of its copies remain const forever. Is that so?


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