Building a Code Editor in Ruby: Gladiator Open Source Project Demo and Architecture

Gladiator, a Ruby-based code editor, offers syntax highlighting, find/replace, and split-pane functionality.

### Building a Code Editor in Ruby: The Gladiator Project
* 💻 **Andy Maleh**, a senior full-stack developer with over 30 years of programming experience, presented his Ruby-based code editor, Gladiator.
* 👨‍💻 He chose Ruby for its object-oriented nature, dynamic typing, and support for meta-programming and embedded DSLs, highlighting its productivity similar to Rails.
* ⚙️ Gladiator's architecture uses **MVC and MVP patterns**, along with design patterns like command, composite, adapter, and observer, and leverages the Glimmer GUI DSL.
* 🧰  The editor is built using **JRuby** to integrate with Java libraries like SWT, and utilizes Ruby gems such as Glimmer DSL, SWT, FileWatcher, and Clipboard.
* 🖥️  Gladiator features syntax highlighting for over 30 languages, find and replace, file tree navigation, a scratchpad, multiple tabs, split panes, and keyboard shortcuts.
* 🗂️ The file tree navigation component is built using Glimmer DSL for SWT, mirroring the GUI structure with declarative code, and utilizes data binding for efficient population.
* 🔍 The file lookup list uses data binding for bidirectional updates between the UI and model, and includes listeners for keyboard and mouse actions.
* 🔄 The development process involved incremental feature additions, starting small and using Gladiator itself for further development, following a flexible "Glimmer process" with seven guidelines.

### Building a Code Editor in Ruby with Glimmer
* 📌 **MVC Pattern** implementation keeps code clean; a single line updates the model, triggering other code to open files in new tabs.
* 📌 **Drag-and-drop** functionality simplifies screen splitting and opening new editors; bidirectional data binding keeps scrolling synced between editors.
* 💻 The **text editor** features line numbers, styled text (like HTML), and data binding for attributes like `topPixel` to synchronize scrolling.
* 💻 **Syntax highlighting** uses the Rouge library, lexing text into tokens and styling them based on language (e.g., Ruby, Markdown, Crystal).  Over 100 languages are supported by Rouge.
* 🗂️ **Tabs** are managed by a tab folder, allowing for creation, dragging, dropping, and closing of tabs; Ruby's methods simplify tab management compared to HTML.
* ⌨️ **Keyboard shortcuts** use a `verifyKey` listener to trigger commands (like indent, undo, redo) before characters appear on the screen; undo/redo uses the command pattern.
* ⚙️ **Running Ruby code** uses `load` instead of `eval` for cleaner code; a separate thread monitors the file system for changes using the File Watcher gem.
* ✨ **Future features** include file content search, themes, a more formal extension process, and improved Windows/Linux support.

How I Built My Code Editor in Ruby by Andy Maleh (Montreal.rb Ruby Talk 2022/07)

Glimmer - Ruby DSL Framework for GUI & More

The code editor was built using Ruby (JRuby), object-oriented design, and various design patterns.

Speaker's background: Bachelor and Master's degrees in Computer Science and Software Engineering; experience at Lexap.

Reasons for building the editor in Ruby: Ruby's strengths as a language (object-oriented, dynamically typed, expressive).

Speaker's extensive programming experience and proficiency in various software development aspects.

Motivation to create a world-class code editor written in Ruby.

Demonstration of Gladiator's features: syntax highlighting, find and replace, file navigation, and scratchpad.

Additional features showcased: file manipulation (delete, create, copy-paste), menu options, split pane functionality, and keyboard shortcuts.

Discussion of basic coding functionality, analytics display, and line jumping.

Addressing audience questions about UI rendering library and cross-OS compatibility.

Software Architecture and Development Process

Gladiator's architecture: GUI app using MVC and MVP patterns, decomposed into software modules.

Software development process: incremental feature development, using Gladiator itself for further development.

The 'Glimmer process': seven guidelines for software development, focusing on small releases and iterative improvements.

Addressing audience questions about external testing and refactoring practices.

Implementation Details: File Tree Navigation

File tree navigation component built using Glimmer DSL for SWT, leveraging the SWT library used in Eclipse IDE.

Use of JRuby to integrate Java libraries with Ruby.

Declarative coding style using Glimmer DSL, similar to HTML structure.

Data binding for efficient tree population.

Use of the composite pattern in the tree structure.

File lookup list component: using Glimmer GUI DSL, data binding, and listeners for user interaction.

Explanation of MVC pattern implementation and bi-directional data binding.

Drag and drop functionality: simplified using Glimmer's features and event handling.

Text editor component: styled text widget, data binding for attributes, and synchronization.

Tabs implementation: using tab folder and tab items, with drag and drop support.

File system monitoring using the FileWatcher gem and multi-threading.

Saving and loading open files using a YAML configuration file.

Future features: file content search, themes, extensions, and improved cross-platform support.

Syntax highlighting implementation using the Rouge library.