La fonction de suggestion automatique permet d'affiner rapidement votre recherche en suggérant des correspondances possibles au fur et à mesure de la frappe.
No, you can not use function or variable as a second parameter. Even some of the filters like default, will also not work in this case as that accepts the second parameter as a string not variable.
But here is a solution for your requirement, that you might use -
{% set zip = personalization_token("contact.city") %} {% set city = personalization_token("contact.city", "Your Town") %}
<p>Your City {% if zip is string_containing "contact.city" %} {{ city }} {% else %} {{ zip }} {% endif %}</p>