Diffrent instance of class share static array member?

[Brian Hsu]

Hello, everybody

When I tried to program an knight problem, I use a loop to test every case, but only the answer of first case is correct. After print some variable, I suspect it is caused by static array member.

So I wrote a simplest code to test, it looks like following (full code is in the attachment), I found that every instance seems share the same array even another instance changed the elements in array.

class TestArray {
    int [] x = [0,0,0,0,0];
    void doSomething () { // Increase every element in array by 1}
}

void main ()
{
    for (int i = 0; i < 5; i++) {
        TestArray t = new TestArray();
        t.doSomething();
        // Print array.
    }
}

I tried gdc/dmd at Linux/Windows all have same result, so I wondered is this a design rationale for memory space and efficiency?

Currently I use add an constructor and in the constructor do x = x.dup in order to create an whole new dynamic array which only belong to specific instance, is my method correctly?

--
Brian Hsu

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