title: Why not overload operator+=() for std::vector?
body: <p>I've started learning C++, so I don't know in my lack of knowledge/experience why something so seemingly simple to a rookie as what I'm about to describe isn't already in the STL. To add a vector to another vector you have to type this:</p>
  
  <pre><code>v1.insert(v1.end(), v2.begin(), v2.end());
  </code></pre>
  
  <p>I'm wondering whether in the real world people just overload the += operator to make this less verbose, for example to the effect of</p>
  
  <pre><code>template &lt;typename T&gt;
  void operator+=(std::vector&lt;T&gt; &amp;v1, const std::vector&lt;T&gt; &amp;v2) {
      v1.insert(v1.end(), v2.begin(), v2.end());
  }
  </code></pre>
  
  <p>so then you can</p>
  
  <pre><code>v1 += v2;
  </code></pre>
  
  <p>I also have this set up for push_back to "+=" a single element to the end. Is there some reason these things should not be done or are specifically avoided by people who are proficient in C++?</p>