I have in mind something that looks like this:

  var log_routes = {
      interactive_error: show_in_minibuffer,
      error: dumpln,
      warning: dumpln
  };

  function log (type, text, context) {
      var logfn = log_routes[type] || dumpln;
      logfn(text, context);
  }

Any given function in log_routes receives both the text and a context object.  The context object would
include properties like "buffer" and "window" when relevant.  This means that the interactive context,
"I", could be used also as a log context.