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filter is not described

has_nav_menu filter-hook . WP 4.3.0

Filters whether a nav menu is assigned to the specified location.

Usage

add_filter( 'has_nav_menu', 'filter_function_name_7786', 10, 2 );
function filter_function_name_7786( $has_nav_menu, $location ){
	// filter...

	return $has_nav_menu;
}
$has_nav_menu(true/false)
Whether there is a menu assigned to a location.
$location(string)
Menu location.

Where the hook is called

has_nav_menu()
wp-includes/nav-menu.php 184
return apply_filters( 'has_nav_menu', $has_nav_menu, $location );

Where the hook is used (in WP core)

Does not used.