title: Printing array of arrays, each internal on separate line
body: <p>Showing my interactive irb session:</p>
  
  <pre><code>2.3.0 :005 &gt; ('a'..'c').to_a.combination(2).to_a
  =&gt; [["a", "b"], ["a", "c"], ["b", "c"]]
  
  2.3.0 :006 &gt; ('a'..'c').to_a.combination(2).to_a.each do |arr|
  2.3.0 :007 &gt;     puts arr
  2.3.0 :008?&gt;   end
  a
  b
  a
  c
  b
  c
  =&gt; [["a", "b"], ["a", "c"], ["b", "c"]]
  </code></pre>
  
  <p>How can I get this array of arrays to show each internal array on separate line, like so..?</p>
  
  <pre><code>["a", "b"]
  ["a", "c"]
  ["b", "c"]
  </code></pre>