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POusing -> to access a virtual function from an array of objects indices
 

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  1. POusing -> to access a virtual function from an array of objects indices
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    <p>I am currently coding a c++ assignment focusing on the properties of inheritance.</p> <p>There is a base <strong>class gun {}</strong>, and several derived classes:</p> <p><strong>handgun: public gun {}</strong></p> <p><strong>revolver: public handgun{}</strong></p> <p><strong>pistol: public handgun{}</strong></p> <p>As per the current assignment, I have added a <strong>virtual</strong> function <strong>print()</strong> to each of these classes that overrides the previous class's <strong>print()</strong>, adding its unique variables to be printed. For example, gun has <strong>string manufacturer</strong>, handgun has <strong>string grips</strong>, and pistol has <strong>bool semiauto</strong>.</p> <p>Now, my professor wants me to make an array containing 2(two) objects, one object of type <strong>revolver: public handgun</strong> and one object of type <strong>pistol: public handgun</strong>. </p> <p>In the assignment, he says we MUST use this exact code to print out the contents of the array:</p> <pre><code>for(int i=0; i &lt;= numGuns; i++) **gunCabinet[i]-&gt;print();** </code></pre> <p>Now, for my code. The error in question is in bold, right near the bottom.</p> <pre><code>int main() { //declares the revolver and pistol objects revolver Anaconda; pistol M9; //sets appropriate variables for the objects Anaconda.setManufacturer("Smith &amp; Wesson"); M9.setManufacturer("Beretta"); Anaconda.setCaliber(".44 special"); M9.setCaliber("9x19mm Parabellum"); Anaconda.setGrips("Hogue grips"); M9.setGrips("U.S. Military specification grips"); Anaconda.setSights("6x scope"); M9.setSights("U.S. Military specification iron sights"); Anaconda.setLaser(true); M9.setLaser(false); Anaconda.setSingleAction(true); Anaconda.setNumberOfRounds(6); M9.setSemiAuto(true); int numGuns = 2; gun* gunCabinet; gunCabinet = new gun[numGuns]; gunCabinet[0] = Anaconda; gunCabinet[1] = M9; // *(gunCabinet) = Anaconda; //*(gunCabinet + 1) = M9; //gun * gunCabinet[/*numGuns*/2] = {&amp;Anaconda, &amp;M9}; for(int i=0; i &lt;= numGuns; i++) **gunCabinet[i]-&gt;print(); //ERROR ON THIS LINE** //cout &lt;&lt; Anaconda &lt;&lt; endl; //Anaconda.print(); //cout &lt;&lt; M9 &lt;&lt; endl; //M9.print(); return 0; } </code></pre> <p>I have commented out my other attempts at making this work.</p> <p>Now, when I run this, I get an error saying "base operand of ‘->’ has non-pointer type ‘gun’".</p> <p>Unless my professor made a mistake, I assume it is all me on this one. The problem is, I can't figure out what I am doing wrong. I am not necessarily looking for an answer to my homework, rather, is his code valid? And if it is valid, can I have some pointers (no pun intended) on what I am doing wrong? thanks a lot!</p>
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    1. USinsomniac
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    1. COIs your professor a member of the NRA by any chance? :-)
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      1. USPraetorian
 

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