title: Convert a vector of string to a vector of integer
body: <p>The following works as expected:</p>
  
  <pre><code>&gt; as.integer(c("2","3"))
  [1] 2 3
  </code></pre>
  
  <p>but when I try (using the stringr package):</p>
  
  <pre><code>&gt; str_split("55,66,77",",")
  [[1]]
  [1] "55" "66" "77"
  &gt; as.integer(str_split("55,66,77",","))
  Error: (list) object cannot be coerced to type 'integer'
  </code></pre>
  
  <p>Is there any other way to convert a string of form "55,66,77" into the vector with those three numbers?
  I'm a complete newbie and any hint to documentation about this would be highly appreciated.</p>