GridOS — EverybodyCodes

Language support, run, and debug for GridOS inside VS Code.

GridOS is a 2D Turing-machine simulator created by EverybodyCodes. In GridOS, one or more read/write heads move across a character grid following a set of user-defined rules. This extension lets you write, run, and debug GridOS programs without leaving VS Code.

Features

File Types

A .grid file must exist alongside every .gridec file with the same base name (e.g. puzzle.gridec + puzzle.grid).

Syntax Highlighting

Both file types receive full colour support. Shades depend on your active theme; the table below lists the semantic role of each token.

.grid files

.gridec files

Grid Files

A .grid file defines the initial state of the 2D grid and the named starting positions for the heads.

Structure

GRID
<grid content>
POSITIONS
<label> <row> <col>
...

Both keywords must be present. POSITIONS must come after GRID.

Grid content

The lines between GRID and POSITIONS describe the initial cell content. Each character maps to one cell — what you see is what the grid contains. Spaces represent empty cells.

POSITIONS section

Each line below POSITIONS names a starting location for a head:

<label> <row> <col>

• label — a single character that matches a character used in the HEADS command of the .gridec file
• row / col — 0-based integer coordinates into the grid content above

Multiple positions can share the same label (placing multiple heads at the same starting cell).

Example

GRID
###========###
POSITIONS
A 0 0
B 0 13

This grid has one row of 14 characters. Head label A starts at column 0 (the first #) and label B starts at column 13 (the last #). A program using HEADS AB would place one head at each of those positions.

Running and Debugging

Open any .gridec file. A single button appears in the editor title bar. Its icon reflects the last-used action:

• — last action was Run
• — last action was Debug

Clicking the button opens a dropdown with two options:

• Run GridOS Program — executes the program to completion and shows the final grid in the built-in GridOS terminal.
• Debug GridOS Program — starts a VS Code debug session with breakpoint and step support.

The selected action becomes the new default and its icon is shown on the button until you choose the other option.

To start debugging with F5, make sure the active editor is a .gridec file (no launch.json required).

Debugger

Set breakpoints by clicking the gutter next to any rule line. Breakpoints are validated — only lines that contain a rule are accepted.

The GridOS terminal updates on every pause, showing the current grid with head positions highlighted. The Variables panel shows:

• state — current machine state
• step — number of steps executed
• head0, head1, … — position (row,col) and the symbol currently under each head

Live Diagnostics

The extension validates .gridec files on every keystroke and underlines errors:

Language Reference

The full GridOS language reference - including rule syntax, special characters, MOVE directions, multi-head programs, and formatting tips - is available in the official EverybodyCodes tutorial:

https://everybody.codes/gridos/tutorial

Settings

All limits are configurable in Settings → GridOS: