title: Bind r data.frames that contain column(s) of nested data.frames
body: <p>After importing multiple .json files using <code>jsonlite</code> I was looking for ways to bind the resulting data.frames which contained one or more columns which themselves were nested data.frames. 
  I came across the following post <a href="https://r.789695.n4.nabble.com/data-frame-with-nested-data-frame-td3162660.html" rel="nofollow noreferrer">https://r.789695.n4.nabble.com/data-frame-with-nested-data-frame-td3162660.html</a>, which helped highlight the problem. </p>
  
  <pre><code>## Create nested data.frames
  dat1 &lt;- data.frame(x = 1)
  dat1$y &lt;- data.frame(y1 = "a", y2 = "A", stringsAsFactors = FALSE)
  
  dat2 &lt;- data.frame(x = 2)
  dat2$y &lt;- data.frame(y1 = "b", stringsAsFactors = FALSE)
  </code></pre>
  
  <p>None of these work</p>
  
  <pre><code>rbind(dat1, dat2)
  dplyr::bind_rows(dat1, dat2)
  data.table::rbindlist(list(dat1, dat2))
  </code></pre>
  
  <p>I've discovered a few workarounds which I'll post below in case they help others.</p>