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copied!<p>To a great extent, that's someone elevating their own weaknesses to a general rule. There's nothing wrong <em>per se</em> with creating objects using the <code>new</code> operator. What there is some argument for is that you have to do so with some discipline: if you create an object you need to make sure it's going to be destroyed.</p> <p>The easiest way of doing that is to create the object in automatic storage, so C++ knows to destroy it when it goes out of scope:</p> <pre><code> { File foo = File("foo.dat"); // do things } </code></pre> <p>Now, observe that when you fall off that block after the end-brace, <code>foo</code> is out of scope. C++ will call its dtor automatically for you. Unlike Java, you don't need to wait for the GC to find it. </p> <p>Had you written</p> <pre><code> { File * foo = new File("foo.dat"); </code></pre> <p>you would want to match it explicitly with</p> <pre><code> delete foo; } </code></pre> <p>or even better, allocate your <code>File *</code> as a "smart pointer". If you aren't careful about that it can lead to leaks.</p> <p>The answer itself makes the mistaken assumption that if you don't use <code>new</code> you don't allocate on the heap; in fact, in C++ you don't know that. At most, you know that a small amout of memory, say one pointer, is certainly allocated on the stack. However, consider if the implementation of File is something like</p> <pre><code> class File { private: FileImpl * fd; public: File(String fn){ fd = new FileImpl(fn);} </code></pre> <p>then <code>FileImpl</code> will <em>still</em> be allocated on the stack.</p> <p>And yes, you'd better be sure to have</p> <pre><code> ~File(){ delete fd ; } </code></pre> <p>in the class as well; without it, you'll leak memory from the heap even if you didn't <em>apparently</em> allocate on the heap at all.</p>

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