https://github.com/kutyel/what-is-a-monad-ts

Learn what Monads™️ are in TypeScript!
https://github.com/kutyel/what-is-a-monad-ts

applicative fp fp-ts functor js learning-exercise monad monads

Last synced: 7 months ago
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Learn what Monads™️ are in TypeScript!

• Host: GitHub
• URL: https://github.com/kutyel/what-is-a-monad-ts
• Owner: kutyel
• License: mit
• Created: 2020-10-20T10:57:40.000Z (about 5 years ago)
• Default Branch: main
• Last Pushed: 2021-09-08T07:40:51.000Z (about 4 years ago)
• Last Synced: 2025-02-02T01:43:40.531Z (9 months ago)
• Topics: applicative, fp, fp-ts, functor, js, learning-exercise, monad, monads
• Language: TypeScript
• Homepage: https://codesandbox.io/s/monads-in-javascript-d0hgm?file=/src/index.js
• Size: 362 KB
• Stars: 3
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Contributing: CONTRIBUTING.md
  • License: LICENSE
  • Code of conduct: code-of-conduct.md

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README

          
# what-is-a-monad-ts

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Learn what Monads™️ are in TypeScript!

```typescript

/**

 * The `Monad` type class combines the operations of the `Chain` and

 * `Applicative` type classes. Therefore, `Monad` instances represent type

 * constructors which support sequential composition, and also lifting of

 * functions of arbitrary arity.

 *

 * Instances must satisfy the following laws in addition to the `Applicative` and `Chain` laws:

 *

 * 1. Left identity: `M.chain(M.of(a), f) <--> f(a)`

 * 2. Right identity: `M.chain(fa, M.of) <--> fa`

 *

 * Note. `Functor`'s `map` can be derived: `A.map = (fa, f) => A.chain(fa, a => A.of(f(a)))`

 *

 */

export interface Nothing {

  readonly _tag: 'Nothing'

}

export interface Just {

  readonly _tag: 'Just'

  readonly value: A

}


export type Maybe = Nothing | Just

```