Logical Operations in PHP

Let's look at the following code:

php<?php
  $a = 1;
  $b = 2;
  
  if ($a == $b) {
    var_dump(true);
  } else {
    var_dump(false);
  }
?>

As you can see, this code compares variables a and b and, if they are equal, it outputs true to the console, and if not - then false.

It's time to reveal something non-obvious to you: in fact, the if construct is not mandatory for comparison - the operators themselves like ==, ===, !=, <, > and others return either true, or false as their result.

See the example:

php<?php
  var_dump(1 == 1); // will output true
  var_dump(1 == 2); // will output false
?>

Based on the above, the code from the beginning of the lesson can be rewritten in a simpler way:

php<?php
  $a = 1;
  $b = 2;
  
  var_dump($a == $b);
?>

You can not output the result immediately, but assign it to some variable:

php<?php
  $a = 1;
  $b = 2;
  
  $res = $a == $b;
  var_dump($res);
?>

php<?php
  $a = 2 * (3 - 1);
  $b = 6 - 2;
?>

php<?php
  $a = 5 * (7 - 4);
  $b = 1 + 2 + 7;
?>

php<?php
  $a = 2 ** 4;
  $b = 4 ** 2;
?>