Question

I am using the boost library and my question is about boost::signals.
I have a signal that might call many different slots but only one slot will match the call so I want this particular slot to return true and that the calling will stop.
Is it possible?
Is it efficient?
Can you guys suggest me a better way to do it if it’s not efficient?

Answer 1

After some research I’ve found that in boost documentation they write about Slots that return values.
They suggest to use a different combiner like this:

struct breakIfTrue
{
  template<typename InputIterator>
  bool operator()(InputIterator first, InputIterator last) const
  {
    if (first == last)
      return false;

    while (first != last) {
      if (*first)
        return true;
      ++first;
    }
  }
};

boost::signal<bool(), breakIfTrue> sig;

Now why is that the wrong thing to do?