Problem with Inventory Listing

Hi, I’m new to I7 and am getting stuck with the inventory listing command.

This is the simple code:

Library is a room. The description is "You are in a library". A book is here. The inventory listing of the book is "an old book".

When running this, it produces the following error:

This is the report produced by Inform 7 (build 6G60) on its most recent run through: Problem. You wrote 'The inventory listing of the book is "an old book"' : but this seems to say that a thing is a value, like saying 'the chair is 10'.

The code seems to be correct according to documentation and all other games downloaded that use the inventory listing code, will produce the same error when running. Reinstalling I7 did not fix the problem. I hope that anyone knows what’s going wrong here.

What documentation are you looking at? The “inventory listing” property was dropped from the standard library in release 5T18.

Ok, thanks. I wasn’t aware of that. I was reading several documentation from the internet but they seem to be obsolete.

The correct way to do this in I7 is (see 17.10):

Rule for printing the name of the book while taking inventory: say "old book". 

Thank you very much.