I'm using QPoint as a key in a QHash, and following the documentation, I implemented a global qHash method for QPoint like so:
inline uint qHash(QPoint const &key, uint seed) {
size_t hash = qHash(QPair<int, int>(key.x(), key.y()), seed);
qDebug() << hash;
return hash;
}
I'm using it like this
class HashTest {
public:
QHash<QPoint, QColor> hash;
void addPixel(QPoint pt, QColor color) {
hash[pt] = color;
}
}
The insert still happens correctly, but it's not using my qHash function. Even if I comment out the qHash function, it still inserts. Considering that QPoint is documented as not having a qHash function, is this expected behavior?
EDIT: Minimal Reproducible Example
#include <QDebug>
#include <QGuiApplication>
#include <QHash>
#include <QPoint>
#include <QQmlApplicationEngine>
int main(int argc, char *argv[]) {
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
#endif
QHash<QPoint, int> hash;
QPoint key = QPoint(0, 0);
hash[key] = 3;
qDebug() << hash[key]; // 3
}
CodePudding user response:
qHash for QPoint might not be documented but sure is defined:
Q_CORE_EXPORT size_t qHash(QPoint key, size_t seed = 0) noexcept;