Filling Arrays in PHP

Let's say we have some array:

php<?php
  $arr = [];
?>

Let's fill this array with some elements. It can be done like this:

php<?php
  $arr = [1, 2, 3, 4, 5];
?>

Alternatively, you can initially create an empty array, and then add data to it like this:

php<?php
  $arr = [];
  
  $arr[] = 1;
  $arr[] = 2;
  $arr[] = 3;
  $arr[] = 4;
  $arr[] = 5;
?>

Obviously, this method is not very convenient, especially if there are a lot of elements in the array. Let's rewrite our code so that the array filling is done by a for loop:

php<?php
  $arr = [];
  
  for ($i = 1; $i <= 5; $i++) {
    $arr[] = $i;
  }
  
  var_dump($arr);
?>