c2f4705f23
The hash function is carefully designed to give the same result as the straight-forward implementation of qHash(unordered_map), which we'll probably add at some point, namely: std::accumulate over a container of std::pair. This is one reason to use std:: and not QPair in the implemen- tation of qHash(QHash). The other is that qHash(QPair) uses a bad hash combiner, which may xor out the 'seed' from the result. We can't fix that until Qt 6, but the qHash(std::pair) overload uses the well-known boost::hash_combine algorithm (implemented in Qt as QtPrivate::QHashCombine), so we can use that. I also trust std::pair to work without problems with reference template arguments, while QPair only very recently gained a very basic auto-test for reference parameters. [ChangeLog][QtCore] Added qHash() overloads for QHash, QMultiHash. Change-Id: I90879d8a99cf1aadb6e84ecc0c3704f52f3691da Reviewed-by: Thiago Macieira <thiago.macieira@intel.com> |
||
|---|---|---|
| .. | ||
| animation | ||
| codecs | ||
| global | ||
| io | ||
| itemmodels | ||
| json | ||
| kernel | ||
| mimetypes | ||
| plugin | ||
| statemachine | ||
| thread | ||
| tools | ||
| xml | ||
| corelib.pro | ||