Connecting overloaded signals and slots in Qt 5

qt5-overloaded.cpp

struct Foo {
    void overloadedFunction();
    void overloadedFunction(int, QString);
};

// requires C++14
qOverload<>(&Foo:overloadedFunction)
qOverload<int, QString>(&Foo:overloadedFunction)

// same, with C++11
QOverload<>::of(&Foo:overloadedFunction)
QOverload<int, QString>::of(&Foo:overloadedFunction)

// usage c++11
connect(spinbox, QOverload<int>::of(&QSpinBox::valueChanged),
        slider, &QSlider::setValue);

// usage c++14
connect(spinbox, qOverload<int>(&QSpinBox::valueChanged),
        slider, &QSlider::setValue);
  
// c++11 template  
template<typename... Args> struct SELECT { 
    template<typename C, typename R> 
    static constexpr auto OVERLOAD_OF( R (C::*pmf)(Args...) ) -> decltype(pmf) { 
        return pmf;
    } 
};

// usage 
connect(spinbox, SELECT<int>::OVERLOAD_OF(&QSpinBox::valueChanged), ...)