[Development] QHash for Qt 6

[Kevin Kofler]

Иван Комиссаров wrote:
> Well, every time I use (or try to use) QStringView I encounter the problem
> of missing methods/functionality. The same applies to the Qt containers.

It's funny because I have that issue each time I am forced to work with 
somebody else's STL containers. :-) (Sometimes, <algorithms> can help, e.g., 
to find an element in an std::vector, but its arcane syntax with the pair of 
iterators is a pain compared to just calling a method such as 
QVector::contains.)

        Kevin Kofler