I think you could do this by subclassing the Template::Stash and overriding the new and get, then making a Template::Plugin module to provide the listing function. Looking at the Template::Stash code, it doesn't appear it would be a hugely painful experience, just a bit of a sting.

In reply to Re: Getting all used parameters from a Template::Toolkit template -- try #2 by assemble
in thread Getting all used parameters from a Template::Toolkit template by Corion

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