fp-ts VS io-ts

I think it’s great that functional programming is making its way into traditional imperative languages - even JavaScript (I recently came across https://gcanti.github.io/fp-ts/ as a pretty extreme example)

Elixir/Erlang has function-level pattern matching, which I really like. I’ve yet to see it anywhere else, though my understanding is it came from Prolog.

While I certainly agree, I've found that this is often an indication of too-complex an architecture, and a fundamental re-think being necessary. I've had projects that depend on [fp-ts], which end up incredibly generic-heavy, but still make it entirely through a typecheck(not build- typescript's just worse at that than other tools like esbuild) in seconds-at-worse.

Obviously depends on your organization/project/application, but I do like these things as complexity-smells.

[fp-ts]: https://gcanti.github.io/fp-ts/

Unlike more comprehensive functional libraries like fp-ts, each module can be imported and resolved separately. If you just need options, simply add the option module and you're good to go.

While it's quite abstract, I believe it may be useful to those of you who is interested to learn more about functional programming [in Typescript] and also get more intuition on diverse programming ideas. I use fp-ts as a functional programming library there.

The library for TypeScript that this is influenced by is here:

https://github.com/gcanti/fp-ts

Interesting how both languages with this library converge to a similar syntax, due to heavy use of functions.

Learn something that pays the bill first - nowadays it's Golang/Rust react/typescript. Then you can try some pure fp libs like fp-ts and fp-core.rs, and look through existing scala cats docs. If you'll feel bad about it - that's totally fine and expectable, fp takes a paradigm shift and not that many dev able to shift their brains way of thought due to basic psychological rigidity) (inability to change habits and to modify concepts/attitudes once developed). And that's purely a staffing and management issue - folks hired randoms out of the blue, and called 'em a team.

fp-ts, a library that caters to functional programming in TypeScript, comes with some micro-abstractions that already solve a few of our needs.

Also, don't underestimate how powerful TypeScript can be in capable hands (namely Giulio Canti's). Check out fp-ts, for instance.

You are able to type it using function overloads, an example can be found here - link, line 236.

looks like more ergonomic/focused version of fp-ts[1]

[1] https://gcanti.github.io/fp-ts/

Qué rico. Si tenés chance meté un proceso de code review fuerte, y para el tema de I/O probá a usar https://github.com/Effect-TS/schema ó https://github.com/gcanti/io-ts que les da una solución obvia al tema de "tipos para lo que devuelva el backend", aunque es en realidad mucho más capaz que eso.

My fave is still io-ts (https://github.com/gcanti/io-ts/blob/master/docs/index.md) as I find it more flexible than zod at the ingress. The author is also working on the Effect ecosystem which also looks interesting.

I’ve been using io-ts for this and been very happy with it. [1] It’s similar to Swift’s Coding protocol in case you’re familiar.

[1] https://gcanti.github.io/io-ts/

Yeah, there are a few new concepts and it's not the easiest to pick up right away. The best introduction is here on the main documentation page.

We use https://github.com/gcanti/io-ts/blob/master/Decoder.md which has a very similar interface. It can even be used to mutate the data using https://github.com/gcanti/io-ts/blob/master/Decoder.md#the-parse-combinator.

A good way to significantly improve the reliability of your app is via improving type-safety by moving away from using any to unknown. One relevant example could be when you type your backend responses and when stringifying JSON to using unknown combined with some sort of runtime type checking. It can be done either by using built-in functionality like type guards or using an external library like io-ts, zod or yup.

Usage of TypeBox is similar with io-ts and zod, but it is much powerful and faster than them. Also, TypeBox can generate JSON schema very easily. Therefore, if you're looking for a validator library for new project and not suffering from legacy codes, I think TypeBox would be much better choice than io-ts and zod. TypeBox can totally replace them.

This check can be done with different libraries like: io-ts, typebox, or zod. These libraries allow you to create objects that represent your typescript definitions. Then, these objects can be used at runtime to validate the received data, in addition, you can also convert this object to a Typescript definition to have all the benefits of using typescript. These objects can be called schema validations because they are responsible for the data validation.