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POCopy constructor with pointers
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  1. POCopy constructor with pointers
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    copied!<p>I have recently discovered that when I have pointers within a class, I need to specify a Copy constructor.</p> <p>To learn that, I have made the following simple code. It compiles, but gives me runtime error when performing the copy constructor.</p> <p>I am trying to copy just the value from the pointer of the copied object, but avoiding assigning the same address.</p> <p>So, what's wrong here?</p> <pre><code> class TRY{ public: TRY(); ~TRY(); TRY(TRY const &amp;); int *pointer; void setPointer(int); }; void TRY::setPointer(int a){ *pointer = a; return; } TRY::TRY(){} TRY::~TRY(){} TRY::TRY(TRY const &amp; copyTRY){ int a = *copyTRY.pointer; *pointer = a; } int main(){ TRY a; a.setPointer(5); TRY b = a; b.setPointer(8); cout &lt;&lt; "Address of object a = " &lt;&lt; &amp;a &lt;&lt; endl; cout &lt;&lt; "Address of object b = " &lt;&lt; &amp;b &lt;&lt; endl; cout &lt;&lt; "Address of a.pointer = " &lt;&lt; a.pointer &lt;&lt; endl; cout &lt;&lt; "Address of b.pointer = " &lt;&lt; b.pointer &lt;&lt; endl; cout &lt;&lt; "Value in a.pointer = " &lt;&lt; *a.pointer &lt;&lt; endl; cout &lt;&lt; "Value in b.pointer = " &lt;&lt; *b.pointer &lt;&lt; endl; return 0; } </code></pre> <p>I'll be using this concept for other classes with lots of pointers in it, where I need to copy all values from on object to the other. Copying is initially necessary for this code, so I would like to keep the copying possibility (I won't be hiding the copy constructor as private).</p> <p>Besides, the real class I need to implement has like 10 pointers, and it might be changing with time. Isn't there a somewhat smarter way to have a deep copy constructor in C++?...</p>
 

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