minecraft-brainfuck

Brainfuck interpreter for Minecraft 1.15.2.

How to use

The Program field in the bfi:in storage stores a Brainfuck program inside a list of single characters. Any invalid characters or strings will be ignored.
The Args field in the bfi:in storage contains the arguments to be passed to the Brainfuck program. This must be a list of characters as well.
Start the process by calling the bfi:read/main function and make sure that the executing entity is a player.

Example:

data modify storage bfi:in Program set value ['+', '>', ',', '>', ',']
data modify storage bfi:in Args set value ['1', '2', '3']
execute as @a run function bfi:read/main

To stop the current process, run the bfi:stop function. To reset all scores and storage, use the bfi:reset function.

Configuration

The user can configure how many iterations per tick should be used for parsing the program, input and interpreting the program. The config file is located in bfi.config/functions/config.mcfunction.

Visualization

The interpretation process can be visualized using entities. An entity with the bfi.output tag will have the output in its CustomName. An entity with the bfi.memory tag will have the memory array in its CustomName. The former can be summoned using the bfi:summon/output function, the latter using the bfi:summon/memory function.

For an example visualization, see this video.

To reduce the interpretation speed and make the program easier to visualize, you can reduce the amount of iterations per tick in the config file by decreasing the #bfi.interpret.count.max bfi.const score.

Behavior

This datapack first parses the program, then the arguments and then interprets the program. If at any stage an error occurs, the process is stopped. This can be done manually by using the bfi:stop function.

This interpreter gives the program an 'infinite' tape to the right, which means that too many < operations will lead to an error. Because dynamic list operations in Minecraft take a lot of resources, the tape is increased by a constant value if needed.
Memory values range from 0-255 and can be overflowed: using - on a cell with value 0 will overflow to 255. Vice versa, using + on a cell with value 255 will set the value to 0.
Input can be parsed from any unicode character ranging from 32-127 and 161-255. Any other characters will be ignored. Similarly, the program can contain any character but only the 8 Brainfuck operations will be parsed.