Title: WP_Block_Type::__isset
Published: November 2, 2022
Last modified: August 20, 2026

---

# WP_Block_Type::__isset( string $name ): bool

## In this article

 * [Description](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#description)
 * [Parameters](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#parameters)
 * [Return](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#return)
 * [Source](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#source)
 * [Changelog](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#changelog)

[ Back to top](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#wp--skip-link--target)

Proxies checking for deprecated properties for script and style handles for backward
compatibility.

## 󠀁[Description](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#description)󠁿

Checks whether the corresponding new property has the first item in the array provided.

## 󠀁[Parameters](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#parameters)󠁿

 `$name`stringrequired

Deprecated property name.

## 󠀁[Return](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#return)󠁿

 bool Returns true when for the new property the first item in the array exists,
or false otherwise.

## 󠀁[Source](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#source)󠁿

    ```php
    public function __isset( $name ) {
    	if ( in_array( $name, array( 'variations', 'uses_context' ), true ) ) {
    		return true;
    	}

    	if ( ! in_array( $name, $this->deprecated_properties, true ) ) {
    		return false;
    	}

    	$new_name = $name . '_handles';
    	return isset( $this->{$new_name}[0] );
    }
    ```

[View all references](https://developer.wordpress.org/reference/files/wp-includes/class-wp-block-type.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/7.1/src/wp-includes/class-wp-block-type.php#L400)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/class-wp-block-type.php#L400-L411)

## 󠀁[Changelog](https://developer.wordpress.org/reference/classes/wp_block_type/__isset/?output_format=md#changelog)󠁿

| Version | Description | 
| [6.1.0](https://developer.wordpress.org/reference/since/6.1.0/) | Introduced. |

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