Lang — syntax highlighting for a small DSL

This extension adds support for the lang language in VS Code:

• syntax highlighting for *.lang files (where clauses, types, variables, function-like definitions, etc.);
• example programs in the examples folder;
• tests that exercise every TextMate scope in the grammar.

Usage

• Install the extension (locally from .vsix or from the Marketplace).
• Open a file with the .lang extension — the language will be detected automatically.
• Open a file with the .lang extension — the language will be detected automatically.

Editor Support (LSP)

This extension includes a standalone Language Server Protocol (LSP) binary that can be used with other editors like Neovim, Helix, or Emacs.

Neovim (nvim-lspconfig)

local configs = require('lspconfig.configs')
local lspconfig = require('lspconfig')

if not configs.lang_language then
  configs.lang_language = {
    default_config = {
      cmd = { "lang-language-server", "--stdio" },
      filetypes = { "lang" },
      root_dir = lspconfig.util.root_pattern(".git", "package.json"),
      settings = {},
    },
  }
end

lspconfig.lang_language.setup({})

Helix

Add to your languages.toml:

[[language]]
name = "lang"
scope = "source.lang"
injection-regex = "lang"
file-types = ["lang"]
roots = ["package.json"]
language-server = { command = "lang-language-server", args = ["--stdio"] }

Zed

Add to your settings.json:

{
  "languages": {
    "Lang": {
      "language_servers": ["lang-language-server"],
      "format_on_save": "on"
    }
  },
  "lsp": {
    "lang-language-server": {
      "binary": { "path": "lang-language-server", "arguments": ["--stdio"] }
    }
  }
}

Ensure lang-language-server is in your PATH (install via npm install -g dmezhnov/lang).

Development

From the project root:

• install tools and dependencies (if needed):

mise run install

• generate the grammar and language configuration (and build a .vsix package):

mise run build

• run tests:

mise run test

• run linting (Trunk):

mise run lint

Packaging and publishing

1. Build a .vsix package:

mise run build

1. Publish (requires a configured publisher on the VS Code Marketplace):

mise run publish

Before publishing for real, replace the publisher field in package.json with your own Marketplace publisher identifier.