[Interest] QVectors vs QLists

[Jason H]

> Sent: Wednesday, May 03, 2017 at 1:53 PM
> From: "Konstantin Shegunov" <kshegunov at gmail.com>
> To: "Jason H" <jhihn at gmx.com>
> Cc: "Qt Project" <interest at qt-project.org>
> Subject: Re: [Interest] QVectors vs QLists
>
> I'll throw my 2 cents in, in addition to Sergio's comment on
> iterator-based traversing.
> 
> 1) If you don't absolutely need key ordering, I'd suggest a hash table
> (e.g. QHash) due to the amortized time lookup/insertion. If you use a
> numerical key for the QMap, I'd definitely consider switching to a
> hash to offset the cost of the tree rotations, which is also
> especially useful (I believe) if the value type is copy-heavy.
> 
> 2) Prefer QVector over QList but not fanatically. If your data's
> movable (declared as such) and the size of `void *` (e.g. keeping
> implicitly shared classes' instances) then QList should fare just
> fine.


Thanks both of you, I am putting effort in to use the classes wisely. Aside fro this keys() thing, I think I'm on point, I only use QMap where I need fast min/max/ordered key lookup, else I'm using QVector. My calls to keys() are few, but they happen on large datasets. 

It sounds like I should just use QLists for keys() until Qt6.