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Showing to my Udemy student they can also declare a class constant with a data type if they use PHP 8.3 or newer. By default, this PHP RESTful API project supports PHP 8.2 as the earliest version (so, not compatible with typed class constants) .

src/Validation/UserValidation.php

@@ -1,12 +1,25 @@
 <?php
+/**
+ * @author     Pierre-Henry Soria
+ * @website    https://www.udemy.com/course/build-modern-php-api/
+ * @website    https://ph7.me
+ * @license    MIT License
+ */
 
 namespace PH7\ApiSimpleMenu\Validation;
 
 use Respect\Validation\Validator as v;
 
 class UserValidation
 {
-    // storing the min/max lengths for first/last names
+    /**
+     * Storing min/max lengths for first/last names.
+     *
+     * @internal Since PHP 8.3, typed constant declarations are supported.
+     *    If using PHP 8.3+, can be changed to: 
+     *        private const int MINIMUM_NAME_LENGTH = 2;
+     *        private const int MAXIMUM_NAME_LENGTH = 40;
+     */
     private const MINIMUM_NAME_LENGTH = 2;
     private const MAXIMUM_NAME_LENGTH = 40;
 
@@ -50,4 +63,4 @@ public function isLoginSchemaValid(): bool
 
         return $schemaValidation->validate($this->data);
     }
-}
+}