Cannot get this C++ example migrated to D

[Skippy via Digitalmars-d-learn]

Anyone wanna try converting this C++ example to D?

(I tried, but getting nowhere.. so far).

// --- C++ example - working -----
#include <iostream>
using std::cout;

class test
{
  private:
    int objNo;
    static int objCnt;

  public:
    test()
    {
        objNo = ++objCnt;
    }

    ~test()
    {
        --objCnt;
    }

    void printObjNumber(void)
    {
        cout << "object number :" << objNo << "\n";
    }

    static void printObjCount(void)
    {
        cout << "count:" << objCnt << "\n";
    }
};

int test::objCnt;

int main()
{
    test t1, t2;
    test::printObjCount(); // 2

    test t3;
    test::printObjCount(); // 3

    t1.printObjNumber(); // object number :1
    t2.printObjNumber(); // object number :2
    t3.printObjNumber(); // object number :3

    return 0;
}
// -----------------------

// D code .. not working yet --
module example;
import std:writefln;

class test
{
  private:
    int objNo;
    static int objCnt;

  public:
    this()
    {
        objNo = ++objCnt;
    }

    ~this()
    {
        --objCnt;
    }

    void printObjNumber()
    {
        writefln("object number : %s", objNo);
    }

    static void printObjCount()
    {
        writefln("count: %s", objCnt);
    }
}

// ??
int counter;

// ??
static this()
{
    counter = test.objCnt;
}

int main()
{
    test t1, t2 = new test();

    test.printObjCount();

    test t3;
    test.printObjCount();

    t1.printObjNumber();
    t2.printObjNumber();
    t3.printObjNumber();

    return 0;
}
// --------------------