WordPress at a glance
функция не описана

WP_Query::is_day() public WP 3.1.0

Is the query for an existing day archive?

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

Хуков нет.

Возвращает

true/false. Whether the query is for an existing day archive.

Использование

$WP_Query = new WP_Query();
$WP_Query->is_day();

Changelog

Since 3.1.0 Introduced.

Код WP_Query::is_day() WP 5.5.1

<?php
public function is_day() {
	return (bool) $this->is_day;
}