title: Why and when delete copy constructor and operator=
body: <p>As a c++ newbe I wondered why it is usefull to explicitely 'disable' or delete the = operator and copy constructor of a class: </p>
  
  <pre><code>SomeClass&amp; operator=(SomeClass&amp;) = delete;
  SomeClass(SomeClass&amp;) = delete;
  </code></pre>
  
  <p>I guess this makes sence if the class is a singleton. But are there any other situations? (Maybe this has something to do with performance issues?)</p>