HTTP is a stateless protocol. Every request is independent of any other, so there are no "instances" of a page.
It is possible to create sessions by tying requests together using cookies, but from what you've told us that is irrelevant here.
Pregunta
In Perl WWW:Mechanize
would a
$mech->get($url)
and a
$mech->post($url, [ 'field' => "$var"]);
command run on the same or separate instances of a page?
I'm looking up values of form/field IDs and using them to generate the POST command, but it's working.
Solución
HTTP is a stateless protocol. Every request is independent of any other, so there are no "instances" of a page.
It is possible to create sessions by tying requests together using cookies, but from what you've told us that is irrelevant here.