title: TypeError: (intermediate value) is not iterable
body: <p>I turn my code to class, it now return some error. that i dont know what is this. i tested already without wrapper into class, the code working. what is this exactly?</p>
  <blockquote>
  <pre><code>TypeError: (intermediate value) is not iterable
  </code></pre>
  </blockquote>
  <pre><code>const mysql = require('mysql2');
  const options = require('../config/database');
  
  class Mysql
  {
      pool;
  
      createPool(options)
      {
          this.pool = mysql.createPool(options).promise();
      }
  
      async execute(query, parameter)
      {
          try 
          {
              const [rows,fields] = this.pool.execute(query, parameter);
  
              return [rows,fields];
          }catch(e)
          { 
              console.log(e.code);
          }      
      }
  }
  
  const client = new Mysql;
  
  client.createPool(options);
  
  (async () =&gt; {
    const [rows] = await client.execute(&quot;SELECT * FROM media&quot;);
  
    console.log(rows);
  })();
  </code></pre>