WordPress at a glance
function is not described

WP_Comment::__isset() public WP 4.4.0

Check whether a non-public property is set.

If $name matches a post field, the comment post will be loaded and the post's value checked.

It's a method of the class: WP_Comment{}

No Hooks.

Return

true/false.

Usage

$WP_Comment = new WP_Comment();
$WP_Comment->__isset( $name );
$name(string) (required)
Property name.

Changelog

Since 4.4.0 Introduced.

Code of WP_Comment::__isset() WP 5.5.1

<?php
public function __isset( $name ) {
	if ( in_array( $name, $this->post_fields, true ) && 0 !== (int) $this->comment_post_ID ) {
		$post = get_post( $this->comment_post_ID );
		return property_exists( $post, $name );
	}
}