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copied!<p>Yes, this is fine so long as the type of the pointer matches what's actually being pointed to in the array. By incrementing a pointer you are performing pointer arithmetic.</p> <p>It may be interesting to note that because iterators in the Standard Library are written to look & feel like pointers in many ways, and all the Standard Library algorithms take iterators specified as template parameters, it is legal and well-defined to use these algorithms with raw pointers as well. For example, this is perfectly legitimate, even with your pointers:</p> <pre><code>const size_t num_data = sizeof(data)/sizeof(data[0]); std::copy( &data[0], &data[num_data], ostream_iterator<QString>(cout,"\n") ); </code></pre> <p>...assuming of course you have implemented <code>operator<<</code> for a <code>QString</code> object.</p> <p>Now, all this being said, take a look at this:</p> <pre><code>QString data[100]; </code></pre> <p>The <code>100</code> here is what's called a <a href="http://en.wikipedia.org/wiki/Magic_number_%28programming%29" rel="nofollow">Magic Number</a>. The use of Magic Numbers is widely considered to be an <a href="http://en.wikipedia.org/wiki/Anti-pattern" rel="nofollow">anti-pattern</a>, or a bad practice. Ask yourself a couple questions:</p> <ol> <li>How do you know that 100 elements will be enough?</li> <li>If you don't need 100 elements, are you being wasteful?</li> <li>If you need more than 100 elements, will your program crash?</li> </ol> <p>It's best to avoid using magic numbers wherever you can. Your choice of <code>100</code> here is arbitrary. It would be better to use a collection type that grows and shrinks as you add and remove objects. <code>std::vector</code> is a good place to start:</p> <pre><code>std::vector<QString> data; </code></pre> <p>Now you can add items:</p> <pre><code>data.push_back( ... ); </code></pre> <p>...remove them, and iterate easily, using iterators:</p> <pre><code>std::copy( data.begin(), data.end(), ostream_iterator<QString>(cout,"\n") ); </code></pre>

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