title: Assign a default value std::function
body: <pre><code>class A{
  private:
   typedef std::function&lt;void(A*)&gt; Myfunction;
   Myfunction actionEvent;
  public:
    A(){
  
  actionEvent={std::cout&lt;&lt;"Hello"};
  //declare a default function value here
  
  };
  void executeAction(){
  this-&gt;actionEvent(this);
  }
  }
  </code></pre>
  
  <p>How to assign a default value in the constructor to myfunction?</p>