title: using a string in a math equation in Dart
body: <p>I store various formulas in Postgres and I want to use those formulas in my code. It would look something like this:</p>
  
  <pre><code>var amount = 100;
  var formula = '5/105'; // normally something I would fetch from Postgres
  var total = amount * formula; // should return 4.76
  </code></pre>
  
  <p>Is there a way to evaluate the string in this manner? </p>