title: Prolog: Reverse function of string_to_list
body: <p>I know the Prolog-builtin "string_to_list". Now i need to reverse its functionality.</p>
  
  <pre><code>?- string_to_list('a*1+2', L).
  L = [97, 42, 49, 43, 50].
  </code></pre>
  
  <p>How can i reverse this? Is there a builtin function?
  Anything that does what "desiredfunction" does, would be a great help.</p>
  
  <pre><code>?- desiredfunction([97, 42, 49, 43, 50], R).
  R = 'a*1+2'.
  </code></pre>
  
  <p>Thank you.</p>