React Advanced

React Advanced 2023

Zotter is a powerful tool for working with TypeScript in React applications, providing a simple schema concept for validation. It allows you to convert Zod schemas into TypeScript types and check if objects match the schema. Zod can be used for validation and contract enforcement, ensuring data consistency and preventing issues. It can also be used in React applications to create a validation layer and prevent code from running with incorrect data. The speaker encourages questions and provides contact information for further discussion.

Many Javascript developers have added typescript to their projects in the last few years. But how many of them are sure of their types at runtime? Can types be guaranteed on runtime too? Using Zod that can be realized! Let's see together how we can use Zod to improve the awareness of our code during its execution and prevent strange mistakes or a bad user experience.

Zod === TypeScript, but at Runtime in Your React Applications

Luca Del Puppo

TS Congress

TypeScript Congress 2023

The Talk discusses the limitations of TypeScript and the lies we tell ourselves about its type safety. It explores examples of unsafe operations and bending the type system using keywords like type assertion and function is dice. The Talk also covers catching syntax errors, type mismatches, and the complexity of conditional types and generics. It emphasizes the importance of understanding TypeScript's limitations and making well-informed decisions as software engineers.

How safe is TypeScript's type safety? How much can you trust your statically typed code? Can you even consider TypeScript's type system "strong"? In this talk, we look at situations where TypeScript fails badly and learn why things have to be that way. We talk about trade-offs, workarounds, and ultimately solutions for all the damn, terrible lies we tell ourselves when using TypeScript.

The Lies We Tell Ourselves Using TypeScript

 Stefan Baumgartner

This talk explores the challenges of building CLIs and introduces a fully typed CLI framework built with TypeScript. It discusses the complexities and pitfalls of CLI implementation and the benefits of using decorators for metadata and logic. The talk also covers type inference challenges and presents a third way of assigning annotations as decorators. It highlights the integration of Tpanion, Zod, and ClipAnion for type checking and format validation. Finally, it mentions other CLI frameworks like ClipAllian, Common.js, and Oclif that offer similar functionality.

In this talk, we will explore the various issues encountered when building JavaScript CLIs, and demonstrate how TypeScript can address them and help us make our applications safer. By the end of this talk, you'll understand how to abstract runtime validations type behind easy-to-use interfaces, and have all the tools you need to bring those benefits into your own CLIs at little cost - whether they are open-source projects, or internal tools.

How to make our CLIs safer with types?

Maël Nison

Hi, everyone. Today, I'll be showing you some of the features that modern frameworks implement or frameworks that leverage Typescript implement to improve the developer and user experience. I'll cover some of the features that Expo with Expo Router and Next.js with the AppRouter implements. Let's talk about setting up TypeScript in both Expo and Next.js. Both frameworks provide a TypeScript-first development experience. The most important feature is type safe routing, which enhances developer productivity and app stability. Frameworks provide a built-in link component for link generation. It reduces the risk of typos and throws type errors when linking to non-existent routes. In Expo, enable the .typed experiment and import the link component from the exporouter package. Expo supports static and dynamic routes, and throws errors for incorrect parameters. ExpoRouter provides hooks like UseSegments and UseRouter for more control. In Next.js, enable typedRoutes in the next config file. We can import the link component from the next link package and restart the dev server after updating the next config file. Next.js automatically generates route definitions and includes the type file in the TS config. Autocompletion is available for the href attribute, which can be a string or dynamic value. Next.js provides hooks like use router for static navigation and router.push to prevent redirection to broken routes. Catch all routes in type safe routing pose a challenge for enforcing type safety on the href attribute. TypeScript may not throw an error for routes that may be broken or lead to unwanted pages. Keep this in mind when working with catch all routes. Before a production build, route types should be in place to ensure accurate type definitions. Generating routes is an ongoing task that needs to happen at the right moment to avoid build-time errors. When implemented correctly, type-safe routes can elevate the developer experience by preventing broken links or dysfunctional routes. In Next.js, server components and client components have different limitations. Next.js provides automatic error checking for importing useState in server components and enforces the useClientDirective to prevent using client-related code in the wrong places. Next.js also ensures type safety by throwing errors for invalid segment config options and requiring the alt attribute for image components to improve accessibility. Config files in Expo and Next.js have different approaches to incorporating TypeScript, with Expo using the TS node require hook and Next.js supporting type checking through jsdoc in the config JS file. By enabling type-safe routing, we catch potential issues at compile time, ensuring robust routes and unbroken links. Many other frameworks and tools leverage TypeScript to empower developers and deliver error-free experiences to users.

TypeScript goes beyond annotating syntax. We’ll explore how modern frameworks leverage type-safety at the project-level to empower better architecture, greater stability, and higher velocities.

#type safety