title: Print a large list of lists
body: <p>I have a dataset that's ~4GB+.</p>
  
  <p>The structure is</p>
  
  <pre><code>UniqueID    Tags
  1           1, 37, 284
  2           1, 284
  3           234, 456, 789
  ...
  </code></pre>
  
  <p>I want to write this to a file, however it's giving me an issue since</p>
  
  <pre><code>typeof(structure) = list
  </code></pre>
  
  <p>and </p>
  
  <pre><code>typeof(structure$Tags) = list
  </code></pre>
  
  <p>I'm hoping to write it to a table exactly as pictured, with 1 column being the UniqueID, and the next column being that second list printed out.</p>
  
  <p>When I attempt to write it currently using </p>
  
  <pre><code>write.table(structure, output_file, sep="\t", row.names=FALSE,col.names=TRUE,quote=FALSE)
  </code></pre>
  
  <p>I get</p>
  
  <pre><code>Error in .External2(C_writetable, x, file, nrow(x), p, rnames, sep, eol,  : 
  unimplemented type 'list' in 'EncodeElement'
  </code></pre>
  
  <p>Which I am pretty sure is due to my table having a list within it.</p>
  
  <p>Edit : I should add, I tried doing 
      structure$tags = paste(structure$tags, collapse="") </p>
  
  <p>but then my result is saved with the format </p>
  
  <pre><code>"c(Tag1, Tag2, ..., TagN)"
  "c(Tag1, Tag284, ... )"
  </code></pre>