title: static mutable member variables in C++?
body: <p>why or for what reason is it not possible to declare a class member variable in C++ as <code>static mutable</code>? Something like</p>
  
  <pre><code>static mutable int t; //This won't compile
  </code></pre>
  
  <p>For me, there is no reason to ban such declarations. E.g. for reasons like maintaining a global class-wide statistics, it may be convenient to have static variable that can be altered by (logically) const methods. So either this is sort of a misdesign in C++ and unnecessarily complicated, or there is a practical or theoretical reason which I cannot see.</p>