title: how can you interleave two vectors of differing lengths in clojure
body: <p>What is the simplest way to interleave two vectors with <code>n+1</code>  and <code>n</code> members?</p>
  
  <pre><code>(def a [:a :c :e])
  (def b [:b :d])
  (interleave a b ); truncates to shortest list
  [:a :b :c :d]
  
  ;what I would like. 
  (interleave-until-nil a b)
  [:a :b :c :d :e]
  </code></pre>