How to use signals and slots in Slicer 3d?

QT signalslot is not a mechanism of C++, it's just a C++ library which provides such functionality You can implement it yourself with Rust, or

connect a signal to a slot with connect() and destroy the 741, connection look for just any signal with the correct name and at least the slot's parameter

qt signal and slot connect; signal parameters to the lambda

qt connect signal slot Adding signals to custom QML types; Connecting signals to methods and signals; Signal to signal connect Signal parameters Signals might have parameters