Rulebook

A generalized language for coding (simple) text-based games

Programmatic creation of games requires a decent amount of work, so we created a unique, writable, and readable language to create games in. In most languages, game code requires many defined objects and inter-relationships. With RuleBook, the programmatic creation of a game is as simple as writing the rulebook for the game. The game is defined by different paragraphs in the book, each of which is defined by a set of instructions.

They can be quite simply defined:

Output text:

Say "Hello World".

Get user input to set a variable:

Get variable_name.

Set a variable value:

Set variable_name.

Assignment uses "is":

variable is value.

Notice every statement in RuleBook so far ends with a period ..

If/Else Conditionals:

if condition:
  statement1,
  statement2.
else:
  statement3,
  statement4.

The if/else lines need a : to define; the last statement in each block ends with .; all other statements end with ,.

Conditional Form:

value1 is value2
value1 < value2
value1 > value2

Defining a paragraph:

state choose:

Paragraphs begin with the keyword state and end with a :.

Every rulebook has two obligitory paragraphs:

state init:
  define all your variables here
state finished:
  this is the state your game goes to when done

Transitions between states are formalized by setting the required `next_state` at the end of each state:

next_state is "finished".

Some background: Text-based games can be represented by state machines by a low-footprint Python interpreter, so it is our Python interpreter and C++ language parser that does the heavy lifting.