// NOTE: This is just an implementation of the events idea, actual code is subject to change

// In its own "Event" file:
typedef std::function<void(Unit*)> UnitProc;  // possibly its own class for function composition?

class Event
{
public:
  // ctor
  Event(const UnitFilter &condition, const UnitProc &action, int timesToRun = -1)
  : condProc(condition)
  , execProc(action)
  , runCount(timesToRun)
  {};
  // check and run
  bool run(Unit *pUnit)
  {
    // Check the condition
    if ( !this->isConditionMet(pUnit) )
      return false;

    this->execute(pUnit);

    // decrement the run count, negative value is infinite
    if ( this->runCount > 0 )
      this->runCount--;
  };
  // check condition
  bool isConditionMet(Unit *pUnit)
  {
    if ( this->runCount == 0 || pUnit == nullptr)
      return false;

    // if cond is invalid, then there is no condition
    return !this->condProc.isValid() || this->condProc(pUnit);
  };

  // execute the procedure
  void execute(Unit *pUnit)
  {
    if ( this->execProc && pUnit)
      this->execProc(pUnit);
  };
private:
  UnitFilter  condProc;
  UnitProc    execProc;
  int runCount;
};

// In UnitImpl:
UnitImpl
{
//...
  Vectorset<Event> eventList;
//...
};