Simone Sanfratello

Do TypeScript without TypeScript

What if you could get TypeScript's safety net without migrating your codebase? Learn how to type-check plain JavaScript files using only JSDoc.

Do TypeScript without TypeScript
#1about 2 minutes

The rise of TypeScript and static code checkers

TypeScript has become a highly popular language, evolving from earlier JavaScript static code checkers like JSLint and Flow.

#2about 4 minutes

Understanding the role of explicit types in code

Explicit types help prevent unexpected results from implicit type coercion and define clear contracts for objects and functions.

#3about 4 minutes

Why type checking is not a substitute for tests

Static type checking only addresses code integrity and cannot replace input validation or comprehensive testing for application reliability.

#4about 2 minutes

Exploring the key benefits of adopting TypeScript

TypeScript improves developer experience through better code completion, reduces cognitive load on large projects, and enhances documentation.

#5about 3 minutes

Considering the costs and drawbacks of TypeScript

Adopting TypeScript introduces a required compilation step, configuration complexity, and potential limitations on JavaScript's dynamic capabilities.

#6about 3 minutes

Using JSDoc to get TypeScript benefits without TypeScript

Leverage JSDoc annotations with the TypeScript compiler to enable static type checking directly in JavaScript files, avoiding a full migration.

#7about 12 minutes

Live demo of type checking JavaScript with JSDoc

A practical demonstration shows how to configure a project and use JSDoc annotations to get real-time type checking in plain JavaScript files.

#8about 14 minutes

Audience Q&A on JSDoc, testing, and configuration

The speaker answers audience questions about JSDoc's limitations with generics, strategies for typed testing, and recommended tsconfig.json settings.

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