title: Can I automatically add functions called using pkg::fct to the importFrom section in roxygen2?
body: <p>When I write a package, I usually call external functions using <code>pkg::fct()</code> just to make it very clear and explicit where the function is coming from. I'm aware of the small overhead, but can usually ignore it.</p>
  <p>On the other hand I like it when all external functions appear in the roxygen tags to give an overview of what is used in the function.</p>
  <p>Is there a way to automatically add all functions called via <code>pkg::fct()</code> to <code>@importFrom</code>? And is that a good idea after all?</p>