bp_activity_delete_comment( int $activity_id, int $comment_id )

function bp_activity_delete_comment( $activity_id, $comment_id ) {
	$deleted = false;

	/**
	 * Filters whether BuddyPress should delete an activity comment or not.
	 *
	 * You may want to hook into this filter if you want to override this function and
	 * handle the deletion of child comments differently. Make sure you return false.
	 *
	 * @since BuddyPress 1.2.0
	 * @since BuddyPress 2.5.0 Add the deleted parameter (passed by reference)
	 *
	 * @param bool $value       Whether BuddyPress should continue or not.
	 * @param int  $activity_id ID of the root activity item being deleted.
	 * @param int  $comment_id  ID of the comment being deleted.
	 * @param bool $deleted     Whether the activity comment has been deleted or not.
	 */
	if ( ! apply_filters_ref_array( 'bp_activity_delete_comment_pre', array( true, $activity_id, $comment_id, &$deleted ) ) ) {
		return $deleted;
	}

	// Check if comment still exists.
	$comment = new BP_Activity_Activity( $comment_id );
	if ( empty( $comment->id ) ) {
		return false;
	}

	// Delete any children of this comment.
	bp_activity_delete_children( $activity_id, $comment_id );

	// Delete the actual comment.
	if ( ! bp_activity_delete( array( 'id' => $comment_id, 'type' => 'activity_comment' ) ) ) {
		return false;
	} else {
		$deleted = true;
	}

	// Purge comment cache for the root activity update.
	wp_cache_delete( $activity_id, 'bp_activity_comments' );

	// Recalculate the comment tree.
	BP_Activity_Activity::rebuild_activity_comment_tree( $activity_id );

	/**
	 * Fires at the end of the deletion of an activity comment, before returning success.
	 *
	 * @since BuddyPress 1.2.0
	 *
	 * @param int $activity_id ID of the activity that has had a comment deleted from.
	 * @param int $comment_id  ID of the comment that was deleted.
	 */
	do_action( 'bp_activity_delete_comment', $activity_id, $comment_id );

	return $deleted;
}