title: Access variable value where the name of variable is stored in a string
body: <p>Similar questions have been raised for other languages: <a href="https://stackoverflow.com/questions/2911442/access-variable-value-using-string-representing-variables-name-in-c">C</a>, <a href="https://stackoverflow.com/questions/2363405/t-sql-get-variable-value-from-string-with-variable-name">sql</a>, <a href="https://stackoverflow.com/questions/1655504/use-variable-value-to-get-value-stored-in-other-variable">java</a>, etc.</p>
  
  <p>But I'm trying to do this in R. </p>
  
  <p>I have:</p>
  
  <pre><code>ret_series &lt;- c(1, 2, 3)
  x &lt;- "ret_series"
  </code></pre>
  
  <p>How do I get <code>(1, 2, 3)</code> by calling some function / manipulation on <code>x</code>, without direct mentioning of <code>ret_series</code>?</p>