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Start of Chapter 4: Kinds |
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Back to §4.1. New kinds |
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Onward to §4.3. Degrees of certainty |
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§4.2. Using new kinds
This seems a good point to see what we can do with new kinds. Here we invent a new kind to provide a new sort of room:
Any dead end that we make is also a room, so it has all of the properties and behaviour of a room. For instance, every room is either "lighted" or "dark", and the default is to be lighted. But we can reverse that convention for dead ends, and we can also fill in some other properties:
A dead end is a kind of room with printed name "Dead End" and description "This is a dead end. You'll have to go back the way you came." A dead end is usually dark.
The Undertomb is a dark room. East is a dead end. South is a dead end with printed name "Collapsed Dead End". Northwest is a dead end called the Tortuous Alcove.
As a result of this, three different rooms adjoin the Undertomb, all dead ends. This is much more concise than spelling them out one at a time would be.
Inform often doesn't mind in what order it is told about the world, but it may need to know the name of a kind before that kind can be used. For example,
A coffer is a kind of container. In the Crypt is an open coffer.
makes sense to Inform and results in the creation of a new thing, just called "coffer" in the absence of any other name to give it, whose kind is "coffer" and which is initially open. Whereas if Inform reads:
without knowing that "coffer" is a kind, it simply makes a thing called "open coffer" (and which is not a container). Inform has to be careful like this: English is simply too overflowing with multiple meanings. An "open railway ticket", for instance, is not a "railway ticket" that one can put objects into.