title: How move map to other map
body: <pre><code>std::map&lt;long long, std::unique_ptr&lt;A&gt;&gt; listOf1;
  std::map&lt;long long, std::unique_ptr&lt;A&gt;&gt; listOf2;
  </code></pre>
  
  <p>how can i add listOf1 to listOf2?
  Probably it's tricky because value is unique_ptr.
  Normall solution:</p>
  
  <pre><code>listOf2.insert(listOf1.begin(), listOf1.end());
  </code></pre>
  
  <p>doesn't work and give error</p>
  
  <blockquote>
    <p>Severity  Code    Description Project File    Line    Source  Suppression State
    Error   C2280   'std::pair::pair(const std::pair &amp;)': attempting to reference a deleted function    c:\program files (x86)\microsoft visual studio 14.0\vc\include\xmemory0 737 Build   </p>
  </blockquote>