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Ensuring compilation error while passing null pointer to a function (3 answers)
Closed yesterday.
I am looking for a way to protect a class from receiving a NULL pointer at compiler time.

class B
{
   // gives some API

}

class A
{

    private:
        B* ptrB_;
    
    public:
        A(B* ptrB) 
        {
            // How can I prevent the class to be created with a null pointer?
            ptrB_ = ptrB;
        }

        // multiple member function using: ptrB_ 
        void A::Func1(void)
        {
            if(!ptrB_ )
                rerturn; // I don't want to add it in every function.

            ...

            return;
        }

}

int main()
{
   B tempB = NULL;
   A tempA(&tempB);
}

How can I force user to always pass a pointer (not NULL) to A constructor?
Was looking at constexpr , but this forces to use static , and that's something I am trying to avoid.