title: How can i convert 'X' to '*' and them compute it in dart
body: <p>i am building a calculator app although its working fine but i just want to make it look like this before its is been turn into mathematical expression:
  how do i achieve something like this:</p>
  <pre><code>'5X4' = 20
  instead of using the asterisk sign '5*4' = 20
  </code></pre>
  <p>like i want to be able to replace the string 'X' in background before it's been computed</p>
  <p>i tried this code below:</p>
  <pre><code>final multiply = '5X4';
    final computed = multiply.replaceAll('X','*');
    final result = computed;
  </code></pre>
  <p>if i run the</p>
  <pre><code>print(result)
  </code></pre>
  <p>but if i try
  <code>print(int.parse(result));</code></p>
  <p>the console print out</p>
  <pre><code>Uncaught Error: FormatException: 5*4
  </code></pre>
  <p>how do i fix this?</p>