Writing TypeScript in Monaco Editor

Providing a high-quality TypeScript editing experience in Monaco Editor on the web requires specific configurations. Here are some key tips:

1. Set the Language to TypeScript

When initializing the editor instance, ensure the language is set correctly:

monaco.editor.create(document.getElementById('container'), {
    value: "const x: number = 10;",
    language: 'typescript'
});

2. Add Custom Type Declarations (Typings)

To provide IntelliSense for external libraries or custom interfaces, use addExtraLib. This allows the editor to recognize types that aren’t defined in the current file:

monaco.languages.typescript.typescriptDefaults.addExtraLib([
    'declare class MyLibrary {',
    '    static doSomething(): void;',
    '}',
].join('\n'), 'filename/to/mylib.d.ts');

3. Essential Editor Settings

Common UI settings that improve the developer experience:

• Minimap: Toggle the code overview on the side.
• Theme: Switch between ‘vs’ (light), ‘vs-dark’, or ‘hc-black’.
• Automatic Layout: Enable automaticLayout: true so the editor resizes with its container.

These configurations transform a basic text area into a powerful IDE-like environment right in the browser.