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    <p>There are very few ways a destructor gets called:</p> <p>1) You create an instance of <code>Drawable</code> on the stack, and it falls out of scope. If this is done in a tight loop, the object will fall out of scope and be destroyed at each iteration of the loop. For example:</p> <pre><code>for (size_t i = 0; i &lt; 100; ++i) { Drawable d; } </code></pre> <p>Here, 100 instances of <code>Drawable</code> will be created and destroyed, at the beginning and end of every loop.</p> <p>2) You <code>delete</code> a dynamically-allocated <code>Drawable</code>:</p> <pre><code>for (size_t i = 0; i &lt; 100; ++i) { Drawable* d = new Drawable; delete drawable; } </code></pre> <p>3) You call the destructor explicitly:</p> <pre><code>Drawable* b = new (buffer) Drawable; b-&gt;~Drawable() </code></pre> <p>Note that #3 uses "placement new" and is <em>highly</em> unlikely.</p> <hr> <p>Objects can be destroyed at suprising times when they are in a container such as a <code>vector</code>. Consider:</p> <pre><code>vector &lt;Drawable&gt; drawables; for (size_t i = 0; i &lt; 10000; ++i) { Drawable d; drawables.push_back (d); } </code></pre> <p>You will notice potentially many destructor calls when you run this code. When you <code>push_back</code>, a copy is potentially made and the original (<code>d</code> here) is destroyed. Also, when the <code>vector</code> reaches capacity it has to reallocate, which results in every item being copied again, and the originals destroyed.</p> <hr> <p>Objects can also be destroyed at suprising time in the face of temporaries and unexpected copies. Consider:</p> <pre><code>void DoSomething (Drawable d) { } int main() { Drawable d; for (size_t i = 0; i &lt; 1000; ++i) { DoSomething (d); } } </code></pre> <p>This is a naive example because the compiler will likely elide the temporaries in this case. But since <code>DoSomething()</code> takes a <code>Drawable</code> <em>by-value</em> a copy of the original could be made. Depending on other code, the compiler might not even be able to elide this copy.</p>
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    1. POdestructor is called continuesly
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    1. USJohn Dibling
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    1. COThanks for the answer, but neither of the above seems to be my case. I create objects once and they exist till my application shuts down.
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      1. USEdwin Schriek
    2. CO@EdwinSchriek: It *must* be one of the above cases.
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    3. COSee my second edit, could the "this" keyword be the cause?
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