code: func (t *Pot) eachFrom(f func(Val) bool, po int) bool {
  	if t == nil || t.size == 0 {
  		return false
  	}
  	_, beg := t.getPos(po)
  	for i := beg; i < len(t.bins); i++ {
  		if !t.bins[i].each(f) {
  			return false
  		}
  	}
  	return f(t.pin)
  }
docs: // eachFrom is a synchronous iterator over the elements of pot with function f,
  // starting from certain proximity order po, which is passed as a second parameter.
  // the iteration ends if the function return false or there are no more elements.