[MOVE TO TEMPLATES]

Is there a way to add items to the header of a nested template? My template structure is as follows:

themes/templates/Page.ss
themes/templates/Layout/ProductPage.ss

I want to add a javascript file reference to ProductPage.ss as it's the only template that requires the script.

I tried using Requirements in the init function of the ProductPage_Controller, however this won't work.

Would appreciate any help on this.