MAJOR-mode for ObjectScript in EMACs

This is a major-mode for editing .cls files in ObjectScript using treesitter.

Preliminaries

1. Emacs Version: You will need Emacs version 29.1 or greater. This version should ship with tree-sitter, but you will need to install it if it is missing.

2. Get objectscript-major-mode. You'll need to download our major mode for emacs here: https://github.com/intersystems/emacs-objectscript-ts-mode.git

3. Tree-sitter Library Files: You need the library files generated by tree-sitter-objectscript. You can configure Emacs to fetch these automatically from the repository.

   • Add the ObjectScript languages to treesit-language-source-alist. This tells tree-sitter where to find the parser source files. Run the following Elisp for each required language (udl, core, and expr).

     For udl:

     (add-to-list 'treesit-language-source-alist
                  '(objectscript_udl . "(https://github.com/intersystems/tree-sitter-objectscript.git)"
                                        "main" "udl/src")))

You can also add the languages to the alist directly in your configuration file. This should compile the language into an el.gz file which EMACS uses for its progmodes.

4. Additional Grammars: If you plan to write embedded Python, Java, or JavaScript within .cls files and want syntax highlighting, you will also need their respective tree-sitter grammars. You can install these using the treesit-install-language-grammar command, as they are officially supported.

5. Install Grammars: After configuring the sources, run the command M-x treesit-install-language-grammar for each of the following grammars:

   • objectscript_udl
   • objectscript_core
   • objectscript_expr

   This will compile and install the grammars, making them available to the tree-sitter parser.

Installation

Once the preliminary steps are complete, installing the major-mode file is straightforward.

1. Place the objectscript_udl-ts-mode.el file in your Emacs lisp/progmodes/ directory and append .gz to the end so EMACS can read it properly. (Note: MELPA support coming soon so this step will be unnecessary). The location of this directory can vary based on your setup:

   • macOS: /Applications/Emacs.app/Contents/Resources/lisp/progmodes/
   • Windows/Linux: The path may differ.

2. With the file in place, you can now open a relevant file and enable the major-mode by running M-x objectscript_udl-ts-mode.

Default Configuration

To make this major-mode the default for all .cls files, add the following two lines to your init.el file:

(autoload 'objectscript_udl-ts-mode "/Applications/Emacs.app/Contents/Resources/lisp/progmodes/objectscript_udl-ts-mode.el.gz" "A major mode for objectscript." t)
(add-to-list 'auto-mode-alist '("\\.cls\\'" . objectscript_udl-ts-mode))

This configuration will ensure that objectscript_udl-ts-mode is automatically activated when you open a .cls file, overriding the default mode for LaTeX files which can also use the .cls extension.

License

This project provided as-is and is licensed under the MIT License.