GB Assembly for Zed

RGBDS / RGBASM syntax support for Game Boy and Game Boy Color assembly.

Repository name: zed-rgbasm
Zed extension name: GB Assembly
Extension id: rgbasm

Important: replaces the separate Assembly extension

Zed grammars are registered globally by grammar name. Both this extension and DevBlocky/zed-asm would otherwise own a grammar named asm.

For that reason, do not install both extensions at the same time.

This extension owns asm once and exposes two languages:

• Assembly — .asm, .s, .S
• GB Assembly — .rgbasm and .rgbinc

You keep normal Assembly syntax support while gaining a separate RGBASM file type.

Install as a dev extension

1. Uninstall Assembly Language Server / Assembly (DevBlocky/zed-asm).
2. Uninstall any older dev version of GB Assembly.
3. Restart Zed once, so the old global asm grammar is unloaded.
4. Extract this repository.
5. In Zed, run Extensions: Install Dev Extension.
6. Select this repository directory (the directory containing extension.toml).
7. Open examples/demo.rgbasm.

Expected result:

• Language picker contains both Assembly and GB Assembly.
• demo.rgbasm automatically selects GB Assembly.
• .asm, .s, and .S files select Assembly.

Why v0.1.x failed

v0.1.0 registered another grammar named asm, colliding with the installed Assembly extension.

v0.1.1 tried to reference the grammar owned by the other extension. That avoided the collision but did not give this extension a reliable grammar to register its own language against.

v0.2.0 uses one grammar owner and two language definitions, avoiding both failure modes.

Grammar

The extension pins the same known-working grammar revision used by the DevBlocky Assembly extension:

• RubixDev/tree-sitter-asm
• 04962e15f6b464cf1d75eada59506dc25090e186

The generic grammar is deliberately used only as the parser layer. The GB Assembly language has its own syntax query and its own .rgbasm and .rgbinc file association.

If it still does not appear

Run zed: open log and search for:

• rgbasm
• GB Assembly
• compiling grammar asm
• failed to compile grammar
• failed to load language

The dev-extension card appearing by itself only proves that the extension manifest was discovered; grammar compilation/language registration errors are reported separately in the Zed log.

Important installation note

This extension bundles the asm Tree-sitter grammar itself and provides both Assembly and GB Assembly. Uninstall other extensions that also register a grammar named asm before installing this dev extension. No asm-lsp is required.

For .rgbasm and .rgbinc files, Zed should automatically select GB Assembly.