How do I use wc() in woocommerce?
as what the doc in your link says. 'prevent the need to use globals'. An example would be like this...
code using global.
global $woocommerce;
$customer_country = $woocommerce->customer->get_country();
code not using global
$customer_country = WC()->customer->get_country();
// some servers may not like like this... best is to use variables like $foo = WC(); then use $foo->customer->get_country()...
How to use WC() ? start here...
why must I avoid global?