ts-pattern VS zod

ts-pattern has been a decent band-aid for the lack of native pattern matching, but obviously has downsides that could be avoided if it was built into the language.

https://github.com/gvergnaud/ts-pattern

ts-pattern

With how powerful the type system is you can implement pattern matching via a library pretty convincingly, https://github.com/gvergnaud/ts-pattern is definitely the go-to. That being said pattern matching is hardly a requirement for being ok for implementing compilers.

https://github.com/gvergnaud/ts-pattern might help

There's a proposal to add something like that to JavaScript but it's been stuck in limbo since 2017 although there are libraries like ts-pattern which implement it already.

Zod is an open-source schema declaration and validation library that emphasizes TypeScript. It can refer to any data type, from simple to complex. Zod eliminates duplicative type declarations by inferring static TypeScript types and allows easy composition of complex data structures from simpler ones. It has no dependencies, is compatible with Node.js and modern browsers, and has a concise, chainable interface. Zod is lightweight (8kb when zipped), immutable, with methods returning new instances. It encourages parsing over validation and is not limited to TypeScript but works well with JavaScript as well.

Zod is a TypeScript-first schema declaration and validation library. It helps create schemas for any data type and is very developer-friendly. Zod has the functional approach of "parse, don't validate." It supports coercion in all primitive types.

Link: https://zod.dev/

You can check out their documentation here.

You can learn more about Zod on their website here.

In JS, it's a good idea anyway to use some JSON parsing library instead of JSON.parse.

With Zod, you can use z.bigint() parser. If you take the "parse any JSON" snippet https://zod.dev/?id=json-type and change z.number() to z.bigint(), it should do what you are looking for.

We will validate our input using client-side zod. Zod handles TypeScript-first schema validation with static type inference. This means that it will not only validate your fields, it will also set types on validated fields.

A word of warning: while discriminated unions are very powerful, there's an ongoing discussion on whether discriminated unions should be deprecated and replaced with a different API.

I was first introduced to Zod by Adam Bobrow - a colleague of mine and a dear friend. Adam was sick and tired from JavaScript's brittleness, and about two years ago he started migrating our code base to TypeScript. But that wasn't enough for him. He kept complaining: "What good are my types, if some other service decides to send me bad data and breaks my code?". That's when he discovered Zod.