I have used the above code to throw together a text adventure engine, which is heavily based on the Graphic Adventure Creator.
My first endeavour was the pack-in example game 'King's Ransom', which can be found at:
http://www.glassfractal.com/adventure/KingsRansom.html .
After that, I attempted to convert a game written with GAC, for which I chose 'Manic Badger', by Psychaedelic Hedgehog Software, simply because it had very few conditions. This may be found at:
http://www.glassfractal.com/adventure/ManicBadger.html . According to the author, this was the worst thing that he ever wrote, purely to fulfill a contract, so don't be too harsh.
As a follow-up, I translated 'Saga Of A Mad Barbarian', by the same author, which was a much more well-formed game.
http://www.glassfractal.com/adventure/SOAMB.html.
The engine itself contains everything that was originally in the GAC, with the addition of adjectives and adaptive text (of which there is the tiniest bit in my version of 'King's Ransom'), although, at the moment, the 'SAVE' feature does not appear to work on iPads. I don't know if this is anything to do with Opera, or the settings on my other half's machine, but hopefully I will find out why soon.
The text in the .js file is encrypted to avoid casual code browsers, but I doubt that it would withstand any serious attempts at decoding.
At the moment it is a series of tools written in SpiderBasic, which I will (hopefully) eventually turn into a single application.
The next objective is to actually to write something original with it.
My thanks to Andy Remic for permission to resurrect his work from the dim and distant past.
Edit 17/11/20 - The engine is now finished and I have added a more complete game. The Open Door was released for the Spectrum by Tartan Software and I've messed about with it a bit to test out the more advanced features of the engine.
It can be found at
http://www.glassfractal.com/adventure/TheOpenDoor.html