ANTLR Editor

A robust TypeScript editor component built on Monaco Editor with ANTLR4 integration. Features enhanced error handling, automatic resource cleanup, and stable resizing capabilities.

✨ Key Features

• 🔧 Robust Error Handling: Automatically handles Monaco disposal errors without user intervention
• 🚀 Stable Resizing: Editor maintains cursor position and selection during layout changes
• 🧹 Automatic Cleanup: Prevents memory leaks with intelligent resource management
• ⚡ Performance Optimized: Minimal remounts and efficient provider management
• 🎨 Monaco Integration: Full Monaco Editor features with syntax highlighting and autocomplete
• 📝 ANTLR4 Support: Built-in support for ANTLR4 grammars and tools

📦 Installation

yarn add @making-sense/antlr-editor

For VTL 2.1 Support

yarn add @making-sense/antlr-editor @making-sense/vtl-2-1-antlr-tools-ts @making-sense/vtl-2-1-monaco-tools-ts

🚀 Quick Start

Basic Usage

import { AntlrEditor } from "@making-sense/antlr-editor";
import * as VTLTools from "@making-sense/vtl-2-1-antlr-tools-ts";
import { getSuggestionsFromRange, monarchDefinition } from "@making-sense/vtl-2-1-monaco-tools-ts";

const customTools = { ...VTLTools, getSuggestionsFromRange, monarchDefinition };

const MyEditor = () => {
    const [script, setScript] = useState("");

    return (
        <AntlrEditor
            script={script}
            setScript={setScript}
            tools={customTools}
            height="400px"
            width="100%"
            theme="vs-dark"
            shortcuts={{
                "ctrl+s, meta+s": () => console.log("Save"),
                "ctrl+enter, meta+enter": () => console.log("Run")
            }}
            displayFooter={true}
        />
    );
};

Advanced Usage with Error Handling

import { AntlrEditor, cleanupProviders } from "@making-sense/antlr-editor";

const AdvancedEditor = () => {
    const [script, setScript] = useState("");

    // Manual cleanup for advanced scenarios
    useEffect(() => {
        return () => {
            cleanupProviders();
        };
    }, []);

    return (
        <AntlrEditor
            script={script}
            setScript={setScript}
            tools={customTools}
            height="100%"
            width="100%"
            theme="vs-dark"
            options={{
                lineNumbers: "on",
                minimap: { enabled: true },
                readOnly: false
            }}
            shortcuts={{
                "ctrl+s, meta+s": handleSave,
                "ctrl+enter, meta+enter": handleRun
            }}
            onListErrors={(errors) => {
                console.log("Validation errors:", errors);
            }}
            displayFooter={true}
        />
    );
};

📋 API Reference

AntlrEditor Props

Prop	Type	Default	Description
script	string	''	The script content to display
setScript	(value: string) => void	-	Callback for script changes
tools	Tools	-	Required - ANTLR4 tools configuration
height	string	'50vh'	Editor height (CSS value)
width	string	'100%'	Editor width (CSS value)
theme	string	'vs-dark'	Monaco theme (vs-dark, vs-light, etc.)
options	Monaco.editor.IStandaloneEditorConstructionOptions	{}	Monaco editor options
shortcuts	Record<string, () => void>	-	Keyboard shortcuts
FooterComponent	React.FC<{ cursor: CursorType }>	-	Custom footer component
displayFooter	boolean	true	Whether to show footer
onListErrors	(errors: Error[]) => void	-	Error callback
variables	Variables	{}	Variables for autocomplete
variablesInputURLs	string[]	[]	URLs to fetch variables from
customFetcher	(url: string) => Promise<any>	fetch	Custom fetch function

Tools Configuration

The tools prop requires an ANTLR4 configuration object:

interface Tools {
    id: string; // Language identifier
    initialRule: string; // Starting rule name
    grammar: string; // Grammar definition
    Lexer: Antlr4Lexer; // ANTLR4 Lexer class
    Parser: Antlr4Parser; // ANTLR4 Parser class
    monarchDefinition?: any; // Monaco syntax highlighting
    getSuggestionsFromRange?: any; // Custom suggestions
}

Variables for Autocomplete

const variables = {
    "var1": { "type": "STRING", "role": "IDENTIFIER" },
    "var2": { "type": "INTEGER", "role": "MEASURE" },
    "var3": { "type": "NUMBER", "role": "DIMENSION" }
};

Keyboard Shortcuts

const shortcuts = {
    "ctrl+s, meta+s": () => handleSave(),
    "ctrl+enter, meta+enter": () => handleRun(),
    "ctrl+z, meta+z": () => handleUndo(),
    "ctrl+y, meta+y": () => handleRedo()
};

🛠️ Best Practices

1. Container Sizing

Always ensure the editor container has a defined height:

// ✅ Good
<div style={{ height: "400px" }}>
    <AntlrEditor height="100%" />
</div>

// ❌ Avoid
<div>
    <AntlrEditor height="auto" />
</div>

2. Error Handling

The editor handles Monaco disposal errors automatically, but you can add custom error handling:

const handleErrors = (errors) => {
    // Handle validation errors
    setValidationErrors(errors);
};

<AntlrEditor
    onListErrors={handleErrors}
    // ... other props
/>

3. Performance Optimization

For large scripts or frequent updates, consider debouncing:

const [script, setScript] = useState("");
const [debouncedScript, setDebouncedScript] = useState("");

useEffect(() => {
    const timer = setTimeout(() => {
        setDebouncedScript(script);
    }, 300);

    return () => clearTimeout(timer);
}, [script]);

<AntlrEditor
    script={debouncedScript}
    setScript={setScript}
    // ... other props
/>

4. Theme Management

Support both light and dark themes:

const { isDarkMode } = useTheme();

<AntlrEditor
    theme={isDarkMode ? "vs-dark" : "vs-light"}
    // ... other props
/>

5. Custom Fetch for Authentication

const customFetcher = (url) => {
    return fetch(url, {
        headers: {
            'Authorization': `Bearer ${token}`,
            'Content-Type': 'application/json'
        }
    });
};

<AntlrEditor
    customFetcher={customFetcher}
    variablesInputURLs={["https://api.example.com/variables"]}
    // ... other props
/>

🔧 Development

Storybook

yarn storybook

Test App

# Clone and setup
git clone https://github.com/Making-Sense-Info/ANTLR-Editor
cd ANTLR-Editor
yarn

# Start test app in watch mode
yarn start-test-app

# Link to external project
yarn link-in-app test-app

Testing

Open test-enhanced-editor.html in your browser to test:

• Editor resizing without remounting
• Layout changes and stability
• Error handling and recovery
• Cursor position preservation

🐛 Troubleshooting

Common Issues

1. "InstantiationService has been disposed" errors

   • The editor handles these automatically
   • If you still see them, ensure you're using the latest version

2. Editor not resizing properly

   • Make sure the container has a defined height
   • Check that the height prop is set correctly

3. Memory leaks

   • The editor includes automatic cleanup
   • For manual cleanup, use cleanupProviders()

4. Cursor position lost during resize

   • This is now handled automatically
   • The editor maintains state during layout changes

Debug Mode

Enable debug logging:

// In browser console
localStorage.setItem("debug", "antlr-editor:*");

🌐 Browser Support

• Chrome 80+
• Firefox 75+
• Safari 13+
• Edge 80+

📄 License

Same as the main ANTLR Editor package.

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

📚 Examples

Check out the Storybook stories for comprehensive examples:

• Basic editor setup
• Resizing and layout tests
• Error handling scenarios
• Custom theming and styling