[Development] Upgrading the sources to C++11 keywords (Q_NULLPTR, etc.)

[Marc Mutz]

On Monday 09 February 2015 09:32:56 Marc Mutz wrote:
> > Something like this should work just as well on QVector, right? If you
> > are doing multiple inserts, perhaps you should keep the inserts outside
> > the main vector while you make them, and only at the end do a single
> > std::merge.
> 
> Boom. Enter quadratic behaviour.
> 
> There is Loki::AssociativeVector, but things like the above is why no-one
> is  using it. You only gain if you don't contantly maintain the is_sorted
> invariant.

To make my statement more precise: As soon as you provide insert_sorted, the 
same people who now use QSet + toList + sort() will invariably use it in a 
loop.

Using a plain vector *is* fine. One just need to get over the fact that this is 
not Python and one has to use std algorithms and function objects.

It's not the syntax that's a problem. It's the semantics that need to be 
understood. In this case, *both* algorithmic complexity *and* the cost of non-
locality of reference (which is why QMap is so bad).

-- 
Marc Mutz <marc.mutz at kdab.com> | Senior Software Engineer
KDAB (Deutschland) GmbH & Co.KG, a KDAB Group Company
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