title: vector of const pointers?
body: <p>The following doesn't compile (very verbose error, but basically "cannot be overloaded" and "invalid conversion from 'const void*' to 'void*'").  I can understand why for example push_back() may not compile, as you can't copy/move into a <code>Foo* const</code>, but why doesn't this compile:</p>
  
  <pre><code>#include &lt;vector&gt;
  using namespace std;
  
  class Foo;
  
  int main()
  {
    vector&lt;Foo* const&gt; vec;
  }
  </code></pre>