Detect variable change at run time in C / C ++

Question

I am developing a C ++ library where users / programmers will extend a class BaseClassthat has a method initArray. This method should be implemented by the user / programmer, and it should normally initialize all elements of the array m_arr.

Here is the snipplet modified in this example:

class BaseClass {
     public:

     BaseClass(int n) {
         m_arr = new double[n]; 
         size = n;
     };
     virtual ~BaseClass();

     int size;
     double* m_arr;

     virtual int initArray();
};

Sometimes a user / programmer implements initArraythat does not initialize some m_arr elements. I would like to create a function in my library that checks to see if initArrayall the elements have executed m_arr. This function must be called by the health check service at runtime .

: ? (, NaN Inf), initArray , .

,

---

Edit

, :

// .h:
class MyExample : public BaseClass {
     public:
     MyExample();
     virtual ~MyExample();
     virtual int initArray();
};

// .cpp:
MyExample::MyExample() : BaseClass(3) { }
MyExample::~MyExample() { }
int MyExample::initArray() {
     m_arr[0] = 10;
     //m_arr[1] = 11; // let say someone forgot this line
     m_arr[2] = 12;
     return 0;
}

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Answer 1

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Answer 3

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class BaseClass {
private:
    size_t size;
    auto_ptr< vector< double > > m_arr;

public:
    BaseClass(size_t n) {
        size = n;
     };
     virtual ~BaseClass();

protected:
     virtual auto_ptr< vector< double > > initArray() const;
};

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Answer 4

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Answer 5

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Answer 6

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double * directAccess() {
   if (m_arr_initialized) return m_arr;
   else return 0;
}

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---

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---

edit: ( ) BaseClass. . :

class InitializerInterface
{
   public:
     virtual double get(int element) const = 0; 
}

 BaseClass(int n, const InitializerInterface & initializer) {
     m_arr = new double[n]; 
     size = n;
     for (int i = 0; i < n; i++)
        m_arr[i] = initializer.get(i);
 };

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Answer 7

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Answer 8

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Answer 10

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