A turing-complete logic programming language for writing interactive fiction games.
See the PLIE’21 paper and conference talk here.
cargo run <input file> <output file>
input file defaults to main.yaml, and output file defaults to compiled.js.
Predicates:
- <kitchen> is a room
- <living room> is a room
- <bathroom> is a room
- <bedroom> is a room
- <kitchen> is connected to <living room>
- <living room> is connected to <bathroom>
- <living room> is connected to <bedroom>
- ?A and ?B can be walked between:
or:
- ?A is connected to ?B
- ?B is connected to ?A
Unique facts:
- Player is in ?_
Initial state:
condition:
- Player is in <bedroom>
- <soap> is in <bathroom>
- <TV remote> is in <living room>
- <knife> is in <kitchen>
- <TV> is in <living room>
displays:
You wake up in a cold sweat. You had nightmares
all night, and now you have a horrible headache.
default:
Choices:
Walk from ?A to ?B:
available when:
- Player is in ?A
such that:
and:
- ?B is a room
- ?A is a room
- ?A and ?B can be walked between
displays:
You walk from ?A to ?B.
causes:
- Player is in ?B
Pick up ?Item:
available when:
- Player is in ?Place
- ?Item is in ?Place
displays:
You have picked up ?Item.
causes:
- Player has ?Item
- removes: ?Item is in ?Place
Drop ?Item:
available when:
- Player is in ?Place
- Player has ?Item
displays:
You have dropped ?Item.
causes:
- ?Item is in ?Place
- removes: Player has ?Item
The code above will compile to a JavaScript file which can be played using the runme.html file in the src directory. The logic programming code in the Predicates section determines the rooms of the house and the rules for their connections, whereas the code in the Choices section uses this data to decide which choices the player has available to take.
For full language syntax see the documentation.