constructors, arrays, and new

I have a class with a constructor that needs to be called so it may initalize it's variables (some which are arrays).

if I do:

Code:

---

class_name variable_name[array_size];

---

it doesn't call the constructors but if I do:

Code:

---

class_name *variable_name = new class_name[array_size];

---

it calls the constructors and the world (or at least program) is happy.

Is this suppose to be happening? And is there any way to get the constructors called using the array notation?

Thanks

I built a quick test program to see if a constructor would be called on my system, and it is called in both circumstances. I was only able to figure that out by putting a break point in the constructor though; if set a break at this line:

Code:

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class_name  variable_name[array_size];

---

It would go right to the next line when I tried to trace into it.

As far as which should be happening, I wouldn't be able to tell you.

Ok this is even wierder. I'm finally getting an error message :)

Quote:

---

cc1plus: warnings being treated as errors
bubbletest.cpp: In function `int main()':
bubbletest.cpp:91: warning: deleting array `class Zone zones[5]'

---

BTW compiler:
g++ -v = gcc version 2.95.4 20011002 (Debian prerelease)

I think it's about time to see the source in its entirety.

Entire source is a little big. Here are the class and first part of main (where it is declared)

Code:

---

#include <iostream>
#include <iomanip>

enum dirs { E = 0, NE, N, NW, W, SW, S, SE };

using namespace std;

class Zone
{
  int connections[8];

  public:
    Zone(){
      for (int i=0; i < 8; i++)
        connections[i] = -1;
    }
    void addconn(int p, int z)
    {
      if ( connections[p] == -1 )
      {
        connections[p] = z;
      }
    }

    int getconn(int p)
    {
      return connections[p];
    }
    void setnum(int x)
    {
      num = x;
    }
    int getdir (void)
    {
      for (int i=0; i < 8; i++)
        if ( connections[i] == -1 )
          return i;

      return -1;
    }
};

---

Code:

---

int main(void)
{
  const int size = 80;
  int base = 0;
  int next = 1;
  int dir;
  Zone *zones = new Zone[size];

---

If I change

Code:

---

Zone *zones = new Zone[size];

---

to

Code:

---

Zone zones[size];

---

It produces the following

Quote:

---

bubbletest.cpp: In function `int main()':
bubbletest.cpp:76: warning: deleting array `class Zone zones[80]'

---

Ok made a test program to test it out in a smaller manner and its working as it should

Code:

---

#include <iostream>

using namespace std;
const int Size = 8;

class Test {
  int arr[Size];

  public:
    Test(){
      for (int i=0; i < Size; i++)
        arr[i] = -1;

      cout<<"Test of constructor call"<<endl;
    }
    int get(int x)
    {
      return arr[x];
    }
};

const int Num = 10;

int main(void)
{
  Test t1[Num];
  for (int i=0; i < Size; i++)
  {
    for (int j=0; j < Size; j++)
      cout<<t1[i].get(j)<<' ';
    cout<<endl;
  }
  Test *t2 = new Test[Num];
  for (int i=0; i < Size; i++)
  {
    for (int j=0; j < Size; j++)
      cout<<t2[i].get(j)<<' ';
    cout<<endl;
  }


  delete[] t2;
}

---

Bah the error was because I forgot to remove the delete[] instruction :(

Took that out and tried it again and it seems to be working.

Weird, oh well I guess the planets were all aligned correctly to give me a weird result :)