title: call class as function in c++
body: <p>in python you can define a class A</p>
  
  <pre><code>class A(object):
      .....
  
      def __call__(self, bar):
          #do stuff with bar
          ....
  </code></pre>
  
  <p>which allows me to use it like this:</p>
  
  <pre><code>bar = "something"
  foo = A()
  foo(bar)
  </code></pre>
  
  <p>I would like to do the same thing in c++, but I did not find anything, Is this possible or did I overlook something?</p>