fp-ts

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Functional programming in TypeScript
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**📢 Important Announcement: fp-ts is Joining the Effect-TS Ecosystem!**

We are excited to announce that the `fp-ts` project is officially merging with the Effect-TS ecosystem. This is a significant step forward in the functional programming landscape, bringing together two powerful libraries under one roof. Giulio Canti, the author of `fp-ts`, is being welcomed into the Effect organization, promising an exciting future with enhanced capabilities and support.

**What This Means for New Users:**

Effect-TS can be regarded as the successor to `fp-ts v2` and embodies what would be considered `fp-ts v3`. This merger marks a significant evolution in the library's capabilities, integrating more features and functionalities tailored towards robust, type-safe, and scalable functional programming.

For more details on this merger and what it entails, please refer to the official [announcement here](https://dev.to/effect/a-bright-future-for-effect-455m). Additionally, you can explore more about Effect-TS and its offerings on our [website and documentation](https://effect.website/).

# Introduction

`fp-ts` is a library for _typed functional programming_ in TypeScript.

`fp-ts` aims to allow developers to use _popular patterns and abstractions_ that are available in most functional languages. For this, it includes the most popular data types, type classes and abstractions such as [Option](https://gcanti.github.io/fp-ts/modules/Option.ts), [Either](https://gcanti.github.io/fp-ts/modules/Either.ts), [IO](https://gcanti.github.io/fp-ts/modules/IO.ts), [Task](https://gcanti.github.io/fp-ts/modules/Task.ts), [Functor](https://gcanti.github.io/fp-ts/modules/Functor.ts), [Applicative](https://gcanti.github.io/fp-ts/modules/Applicative.ts), [Monad](https://gcanti.github.io/fp-ts/modules/Monad.ts) to empower users to write pure FP apps and libraries built atop higher order abstractions.

A distinctive feature of `fp-ts` with respect to other functional libraries is its implementation of [Higher Kinded Types](<https://en.wikipedia.org/wiki/Kind_(type_theory)>), which TypeScript doesn't support natively.

**Inspired by**

- [Haskell](https://www.haskell.org)
- [PureScript](https://www.purescript.org)
- [Scala](https://www.scala-lang.org)

# Sponsors

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