[Adventuron] Distinguishing between preposition1 and preposition2

A simple question this time. When testing for the absence of a preposition, am I better off using preposition_is "" or original "preposition" == ""?

Similarly, when testing for the presence of a preposition, am I better off using !preposition_is "" or original "preposition" != ""?

I’ve tested both and both appear to work.

You’ll be pleased to know that I now have a fully functioning book. You can open it and close it, examine it and read it (each giving a different response depending on whether it’s opened or closed). If you read it when it’s open, it gives you a table of contents. You can then read about (or consult book about) anything in the table of contents. You can even consult book about book. If you try to read about anything that is not in the contents (either a word not in the game or a word in the game, but not in the contents), you get a sensible response. Some of this works by adding extra tests to work around the strangeness in the current Adventuron parser.

I’m happy now, as the book is crucial to finding information that is needed to solve puzzles in the game. There are plenty of in-game hints telling you how to use the book. Armed with this knowledge, I will now be able to ask characters about topics.

Incidentally, this is for the Adventuron Christmas Jam. See the intfiction post or the itch.io jam page for further details, if interested.