title: How to extract a single element of list-value of function using dplyr/magrittr - R
body: <p>I'm writing code using <code>dplyr</code> and pipes and using <code>NbClust</code> function, which returns a list of objects named <code>All.index</code>, <code>All.CriticalValues</code>, <code>Best.nc</code>, <code>Best.partition</code>.</p>
  
  <p>So I can assign my expression to some variable and then refer to <code>Best.nc</code> element as a <code>variable$Best.nc</code>. But how can I extract <code>Best.nc</code> element using pipes?</p>
  
  <p>I have tried <code>purrr::map('[[', 'Best.nc')</code> but it didn't work.</p>