is_a

Function • Params and return types changed in PHP 8.0

Checks whether the object is of a given type or subtype.

PHP 5
PHP 7
PHP 8.0
Improved
PHP 8.1-8.2
PHP 8.3
PHP 8.4
PHP 8.5
PHP 8.6

is_a Function synopsis

is_a(
    mixed $object_or_class,
    string $class,
    bool $allow_string = false
  ): bool

Parameters

$object_or_class

Typemixed

A class name or an object instance.

$class

Typestring

The class or interface name

$allow_string

OptionalTypeboolDefault valuefalse

If this parameter set to false, string class name as $object_or_class is not allowed. This also prevents from calling autoloader if the class doesn't exist.

Return value

Typebool

Returns true if $object_or_class is the $class object type, or has $class as one of its supertypes, false otherwise.

Changes to the is_a Function

PHP 8.0

  • Return type added: bool
  • Parameter name of parameter #1 changed: $object to $object_or_class
  • Parameter type added for parameter #1 ($object_or_class): mixed
  • Parameter name of parameter #2 changed: $class_name to $class
  • Parameter type added for parameter #2 ($class): string
  • Parameter type added for parameter #3 ($allow_string): bool
  • Parameter default value added for position #3 ($allow_string): false
  is_a(
-     $object,
+     mixed $object_or_class,
-     $class_name,
+     string $class,
-     $allow_string
+     bool $allow_string = false
-   )
+   ): bool

PHP 5.4

  • Optional parameter added - #3: $allow_string
-is_a($object, $class_name)
+is_a(
+    $object,
+    $class_name,
+    $allow_string
+  )

is_a Function Availability

PHP VersionAvailability
PHP 8.6Future Release Yes
PHP 8.5Upcoming Release Yes
PHP 8.4Supported (Latest) Yes
PHP 8.3Supported Yes
PHP 8.2Security-Fixes Only Yes
PHP 8.1Security-Fixes Only Yes
PHP 8.0Unsupported Yes
PHP 7.4Unsupported Yes
PHP 7.3Unsupported Yes
PHP 7.2Unsupported Yes
PHP 7.1Unsupported Yes
PHP 7.0Unsupported Yes
PHP 5.6Unsupported Yes
PHP 5.5Unsupported Yes
PHP 5.4Unsupported Yes
PHP 5.3Unsupported Yes