code: func (p *leakcheckElemTypePool) CheckExtended(t *testing.T, fn leakcheckElemTypeFn) {
  	p.Check(t)
  	p.Lock()
  	defer p.Unlock()
  	for _, e := range p.AllGetItems {
  		fn(e)
  	}
  }
docs: // CheckExtended ensures there are no leaks, and executes the specified fn