title: Translating C++ member initialisation constructor to Julia
body: <p>I have this class in C++ and want to replicate it in Julia. </p>
  
  <pre class="lang-cpp prettyprint-override"><code>class Clock
  {
    double epsilon;
    double dt;
    int64_t timestep;
    double t;
    Clock(double _epsilon=1e-14) : epsilon(_epsilon)
  };
  </code></pre>
  
  <p>So far I have  </p>
  
  <pre><code>mutable struct Clock
      epsilon::Float64
      dt::Float64
      timestep::Int64
      t::Float64
      #Need the constructor#
  end
  </code></pre>