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POIf a pointer is set to NULL wouldn't any references to it or through it also be NULL
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  1. POIf a pointer is set to NULL wouldn't any references to it or through it also be NULL
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    copied!<p>If a pointer is set to NULL wouldn't any references to it or through it also be NULL. Here is a compilable example that will bomb when you try to run it: </p> <pre><code>#include &lt;string&gt; #include &lt;iostream&gt; #define NULL 0 class Seedcoat { public: //Seedcoat(); std::string Name; int Weight; }; class Seed { public: //Seed(); std::string Name; int Weight; Seedcoat* ItsSeedcoat; }; class Apple { public: //Apple(); std::string Name; int Weight; Seed* ItsSeed; }; int main() { ///////Apple Objects Begin/////// Apple MyApple; Seed MySeed; Seedcoat MySeedCoat; MyApple.ItsSeed = &amp;MySeed; MyApple.ItsSeed-&gt;ItsSeedcoat = &amp;MySeedCoat; MyApple.ItsSeed-&gt;ItsSeedcoat-&gt;Weight = 2; if ( MyApple.ItsSeed != NULL) { std::cout &lt;&lt; "The weight of the apple seed's seedcoat is " &lt;&lt; MyApple.ItsSeed-&gt;ItsSeedcoat-&gt;Weight &lt;&lt;".\n"; } MyApple.ItsSeed = NULL; if ( MyApple.ItsSeed-&gt;ItsSeedcoat != NULL) { std::cout &lt;&lt; "The weight of the apple seed's seedcoat is " &lt;&lt; MyApple.ItsSeed-&gt;ItsSeedcoat-&gt;Weight &lt;&lt;".\n"; } return 0; } </code></pre> <p>So my question is: Why does this </p> <pre><code>MyApple.ItsSeed-&gt;ItsSeedcoat != NULL </code></pre> <p>return true. I would think it would not because ItsSeed is set to NULL - but it still tries to reference the weight value of ItsSeedcoat - and then it bombs I presume because ItsSeed does not exist. I realize there are easy ways to get around this - this example was just to show the behavior I am observing. Is this anything to be concerned about? - or is this normal behavior? What is/are the reason(s) it was done this way? Thanks.</p>
 

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