10 PHP Tricks That Can Save You From Weird Bugs

1. == and === Are Not the Same: PHP has two comparison operators: == and ===. The first compares values, while the second compares both value and type. For example, 5 == 5 outputs true, but 5 === 5 outputs false because 5 is an integer and 5 is a string. It is recommended to use === and !== for more predictable code.

2. The Weirdness of 0, 0, and False: PHP treats several values as false in certain situations. For instance, 0, 0, false, null, [], and an empty string can behave like false. This can cause issues when checking for the existence of a value. To be more specific, use if ($id === null) instead of if (!$id) to check for a missing ID.

3. The Null Coalescing Operator ??: This operator is useful for providing a default value if a variable is null. For example, $username = $_GET['username'] ?? 'Guest'; This will return 'Guest' if the 'username' key doesn't exist. It can also be chained for multiple default values.

4. ?? Is Different From ?: While both operators can appear similar, they have different purposes. Null coalescing ?? checks if a value exists and is not null, while ternary ?: checks if a value is truthy. For instance, $name = $user['name'] ?? 'Guest' will return 'Guest' if the 'name' key doesn't exist or is null. Using ?: instead can lead to unexpected results when checking for specific values like 0 or false.

5. Swapping Variables Without a Temporary Variable: In PHP, you can swap variables without using a temporary variable by using array destructuring. For example, $a = 10; $b = 20; [ $a, $b ] = [ $b, $a ]; This will result in $a = 20 and $b = 10, making the code cleaner and more concise.