# A train puzzle

So, I am new to writing in I7 (if you couldn’t tell by my postcount), and I’ve hit a snag in a project that I would like some help with.

I am trying to create a puzzle where, in order to stage a train robbery, the player has to get said train onto the right track. The way I have it figured out right now, there are a bunch of points along train tracks in one location that can be changed. These points are controlled by switches in a building inside from the larger area, with each pull of a switch changing two specific points along the junction. Where I am getting stuck are these areas:

-Figuring out what the points should be understood as (objects? backdrops? etc.) and how to assign values to them (in this case, whether the rail changes are straight or changed)
-Can a switch only be used to turn something on and off, or can it be used to alter another kind of value?

Basically, I can’t figure out from the documentation how to assign a value to a fixed object and get a switch to change that value. Any help on this would be very much appreciated.

If you want a thing (or a kind of thing) to be able to change between straight and diverging, you just have to state in your source text that it can be straight or diverging.

[code]A set of points is a kind of thing. A set of points can be diverging or straight. A set of points is usually straight.

The first turnout is a set of points .
The second turnout is a set of points [… etc.][/code]

If you make switches a kind of devices, they can automatically be ‘switched on’ or ‘switched off’.

```A switch is a kind of device. The first switch is a switch <in this or that room>. [… etc.] ```

Then you just need a couple of rules that tell what happens to the turnouts as you switch the switches on or off.

[code]After switching on the first switch:
now the second turnout is straight;
now the third turnout is diverging;
continue the action.

After switching off the first switch:
now the second turnout is diverging;
[… etc.] [/code]