15.16. Defining things with tables

| Chapter 15: Tables |

| 15.16. Defining things with tables

Suppose we need to create a collection of items which differ in their properties, but are basically part of a larger pattern. For instance, here we set up what we need to make a collection of coloured shirts:

> A jersey is a kind of thing. A jersey is wearable. A jersey has a number called year established. A jersey has a text called citation. The description of a jersey is "Since [year established], the Tour de France has awarded this jersey to the [citation]."

Now we have the pattern, but making the actual shirts is tedious and repetitive:

> The yellow jersey is a jersey. The year established of the yellow jersey is 1919. The citation of the yellow jersey is "race leader". The polkadot jersey...

And so on. Instead, we can use a table to abbreviate all of this:

> "Tour des Maillots"

> The Staging Area is a room. A jersey is a kind of thing. A jersey is wearable. Some jerseys in the Staging Area are defined by the Table of Honorary Jerseys. The description of a jersey is "Since [year established], the Tour de France has awarded this jersey to the [citation]."

> Table of Honorary Jerseys

> jersey | year established | citation
> a yellow jersey | 1919 | "race leader"
> a polkadot jersey | 1933 | "King of the Mountains"
> a green jersey | 1953 | "highest point scorer on sprints"
> a white jersey | 1975 | "best cyclist aged 25 or less"

The first column provides names for the new things to be created. Subsequent columns provide property values. Note that we did not need to say that jerseys have a number called "year established" because Inform is able to infer this from the column heading and the presence of numbers in the column; similarly for "citation". Lastly, note that if any entry is blank (written "--") then that particular property is simply not set for that particular item.

Note that Inform reads articles such as "the" or "a" in the first column just as it would when something is created with any other sentence.

It's even possible to define kinds this way, though it's rare to need to create many kinds at once. (See the worked example "Reliques of Tolti-Aph" at the Inform website. There's no special syntax needed: rather than saying "Some jerseys are defined by..." we would say "Some kinds of jersey are defined by...")

271
| Example Sweeney A conversation where each topic may have multiple questions and answers associated with it, and where a given exchange can lead to new additions to the list. |
RB

272
| Example Introduction to Juggling Assortment of equipment defined with price and description, in a table. |
RB

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