title: casting data from a loop to 2d array
body: <p>I have an array of data to fetch from firebase, I'm making a for loop to iterate through the data in order to store it in a 2d array with 3 elements for each section ex: <code>[["1","2","3"],["4","5","6"],["7","8","9"]]</code></p>
  
  <p>How do I append to the array and store it as 2d array like the one above with 3 element in each array index ?</p>
  
  <pre><code>@State var array2d: [[]] 
  
      ForEach(Networking.forSalePosts){i in
  //don't know how to append it here :)
  }
  </code></pre>
  
  <p>Thanks</p>