Documentation
Display a field only if it matches a condition
Adding conditions to fields
If you want to hide or show a field on your pass based on a certain condition, you can specify such a condition by using the syntax explained below.
To add a condition, click on “Extended options” when editing a field using the template editor in gifttowallet.

Conditions are fault tolerant to a certain degree. E.g. it doesn’t matter if you add whitespaces after the comparison operator or not or if you enclose a string in double or single quotes. Currently only one condition can be added which means it’s not possible to use “or” conditions.
Show a field if a certain additional property is not empty
To make sure a field is only added to the pass if it contains a value (which means it’s not empty), just enter the placeholder of the additional property in the condition field.
E.g.
{Fieldname}
Entering the placeholder only is the same as comparing it to an empty string:
{Fieldname} != ''
Show a field if an additional property has a certain value
If you only want to display a field on your pass if an additional property contains a specific value, e.g. if the level of a user is “Silver”, you can add the following condition:
{Level} == 'Silver'
Show a field if it does not match a certain value
If you only want to display a field if an additional property does not match a specific value, add a condition like the following:
{Level} != 'Silver'
This is the same as
{Level} <> 'Silver'