TypeScript to JSDoc Converter – Preserve Type Information in JavaScript
When migrating from TypeScript to JavaScript or wanting to add type hints to JavaScript code, the TypeScript to JSDoc Converter transforms TypeScript type annotations into JSDoc comments. This allows you to preserve type information in plain JavaScript while maintaining compatibility with JavaScript-only projects.
JSDoc type annotations provide type checking and IntelliSense support in JavaScript through TypeScript's type checking system, without requiring a TypeScript build step.
TypeScript vs JSDoc Types
TypeScript Types
TypeScript uses inline type annotations with syntax like:
function greet(name: string, age: number): string {
return `Hello, ${name}!`;
}
JSDoc Type Annotations
JSDoc uses comment-based type annotations:
/**
* @param {string} name
* @param {number} age
* @returns {string}
*/
function greet(name, age) {
return `Hello, ${name}!`;
}
Benefits of JSDoc Types
- JavaScript Compatibility: Works in plain JavaScript without compilation
- Type Checking: TypeScript can check JSDoc-annotated JavaScript
- IDE Support: Provides IntelliSense and autocomplete
- Documentation: JSDoc comments serve as inline documentation
- No Build Step: No need for TypeScript compiler
Supported Type Conversions
- Primitive Types: string, number, boolean, null, undefined
- Complex Types: object, array, function, union types
- Optional Parameters: Converted to JSDoc optional syntax
- Return Types: Converted to @returns annotations
Use-Cases
- TypeScript Migration: Converting TypeScript to JavaScript while preserving types
- JavaScript Enhancement: Adding type hints to existing JavaScript
- Type Safety: Getting type checking without TypeScript compilation
- Documentation: Adding self-documenting type information
Conclusion
The TypeScript to JSDoc Converter helps bridge the gap between TypeScript and JavaScript by converting type annotations to JSDoc comments, enabling type checking and IDE support in plain JavaScript files.