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Determine if the slot is connected to the given signal

I'm curious to see if there is a way to determine that there is a connection to a given signal that I have defined in the class. This is basically a signal to process the data and I don't care what it's related to, but I would like to enable a health check so that I don't send data into a void where it will never be seen. I have checked Determine signals connected to a given slot in Qt , but this is kind of the opposite problem.

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QObject::isSignalConnected()

QObject::isSignalConnected()

exactly for usecase - avoids unnecessary work to prepare the signal when no one is listening. Its API docs even come with a good example.

Example:



static const QMetaMethod valueChangedSignal = QMetaMethod::fromSignal(&MyObject::valueChanged);
if (isSignalConnected(valueChangedSignal)) {
    QByteArray data;
    data = get_the_value();       // expensive operation
    emit valueChanged(data);
}
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