Title: wp-includes/class-wp-filter-sentinel.php | Developer.WordPress.org

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# File: wp-includes/class-wp-filter-sentinel.php

 * class[WP_Filter_Sentinel](https://developer.wordpress.org/reference/classes/wp_filter_sentinel/)
 * Marker object used as a filter’s default value when any user value — including`
   null`, `false`, or arbitrary objects — must remain distinguishable from the “
   no filter modified this” case.
 * Used by [0 functions](https://developer.wordpress.org/reference/classes/wp_filter_sentinel/#used-by)
   | Uses [0 functions](https://developer.wordpress.org/reference/classes/wp_filter_sentinel/#uses)
   | Source: [wp-includes/class-wp-filter-sentinel.php:25](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/class-wp-filter-sentinel.php#L25-L25)