Geobe

Geobe is a geometric esoteric programming language interpreter written in Python. Programs are 2D grids of Unicode symbols where arrows control flow and shapes carry semantics.

Overview

Geobe programs are rectangular text grids. The interpreter finds every ○ source node and follows directional flow through the grid until a path ends. The current MVP supports a single deterministic memory cell, input buffering, output collection, and pluggable △ transforms.

Core symbols:

• ○ read the next input value
• □ store the current value in memory
• △ transform the current value
• ▲ change/delta transform the current value
• ▽ append the current value to output
• ◀ append the current value to output
• ▶ traverse the current array by one index
• ▶▶ continue the current array loop, or finish when exhausted
• →, ←, ↑, ↓ move execution through the grid
• «... » read a literal string into the current value
• spell ... decode triangle alphabet symbols into lowercase text output

Spaces are treated as empty cells for traversal. Other non-traversable characters stop a path.

Installation

The project targets Python 3.11+.

#cd into project root:
python3 -m pip install .

Running Programs

Run a .geo file:

geobe examples/input_store_transform_output.geo --input hello

Run inline source:

geobe --code "○→▽" --input hello

Run a literal string program:

geobe --code "«hello, Geobe!»→▽"

Read additional input values from standard input:

printf 'first\nsecond\n' | geobe --code "○→▽\n○→▽" --stdin-input

Start the interactive spelling console:

geobe --console

In console mode, lowercase letters are echoed as Geobe's mapped alphabet symbols. Pressing Enter prints the English equivalent of the current line. For example, typing hello! displays ▹▶▿▿◂!, then Enter prints hello!.

Trace execution as JSON:

geobe --code "○→□→▽" --input hello --trace

Trace execution in readable text:

geobe --code "○→□→▽" --input hello --trace --trace-format text

Running the package module directly executes the built-in demo program:

python3 -m geobe

Example Program

examples/input_store_transform_output.geo

○→□→△→▽

With input hello, the program stores the value, applies the default identity transform, and outputs hello.

Array loop:

○→▶→◀→▶▶

With Python input [1, 2, 3], the program traverses the array and outputs [1, 2, 3].

Spelled text:

spell ▹▶▿▿◂ ◮◂ ◣▿▵!

This decodes to hello world! and outputs it.

Python code can also encode English into the triangle alphabet:

from geobe.parser import encode_spell_text

encoded = encode_spell_text("Hello world!")

Custom Transforms

The △ symbol is backed by a transform registry. The default transform is identity, and you can register your own behavior in Python code.

See examples/custom_transform.py for a minimal example that returns a custom formatted value.

Development

Run the test suite:

pytest

Run linting and type checks:

ruff check .
mypy src tests

Project Layout

• src/geobe/ interpreter, parser, runtime state, and CLI
• examples/ documented sample programs
• tests/ coverage for the CLI, parser, interpreter, and examples

Package Entry Points

• geobe CLI: geobe.cli:main
• Module entry point: python3 -m geobe