title: strsplit with vertical bar (pipe)
body: <p>Here, </p>
  
  <pre><code>&gt; r&lt;-c("AAandBB", "BBandCC")
  &gt; strsplit(as.character(r),'and')
  [[1]]
  [1] "AA" "BB"
  
  [[2]]
  [1] "BB" "CC"
  </code></pre>
  
  <p>Working well, but</p>
  
  <pre><code>&gt; r&lt;-c("AA|andBB", "BB|andCC")
  &gt; strsplit(as.character(r),'|and')
  [[1]]
  [1] "A" "A" "|" ""  "B" "B"
  
  [[2]]
  [1] "B" "B" "|" ""  "C" "C"
  </code></pre>
  
  <p>Here, the answer is not correct. How to get "AA" and "BB", when I use '|and'? <br/>
  Thanks in advance.</p>