WordPress at a glance
filter is not described

woocommerce_get_product_subcategories_cache_key filter-hook . WC 1.0

Get (and cache) product subcategories.

Usage

add_filter( 'woocommerce_get_product_subcategories_cache_key', 'filter_function_name_6855' );
function filter_function_name_6855( $parent_id ){
	// filter...

	return $parent_id;
}
$parent_id
-

Where the hook is called

woocommerce_get_product_subcategories()
woocommerce_get_product_subcategories_cache_key
woocommerce/includes/wc-template-functions.php 2523
$cache_key          = apply_filters( 'woocommerce_get_product_subcategories_cache_key', 'product-category-hierarchy-' . $parent_id, $parent_id );

Where in WP core the hook is used WooCommerce

Usage not found.