https://github.com/fatmatto/resultjs

Result monad for Javascript
https://github.com/fatmatto/resultjs

Last synced: 1 day ago
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Result monad for Javascript

• Host: GitHub
• URL: https://github.com/fatmatto/resultjs
• Owner: fatmatto
• Created: 2021-08-23T09:14:17.000Z (over 3 years ago)
• Default Branch: main
• Last Pushed: 2023-11-27T16:11:44.000Z (about 1 year ago)
• Last Synced: 2025-01-06T23:39:36.387Z (21 days ago)
• Language: JavaScript
• Size: 132 KB
• Stars: 2
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md

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README

        
## Result Monad

Convenient way to handle functions that might return errors without throwing. Heavily inspired by Rust and Golang.

### Usage

```javascript

const {wrap, wrapSync} = require('@fatmatto/resultjs')

// Wrap an async function that might throw

const wrapped = wrap(params => mightFailAsync(params))

// Wrap a sync function

const wrappedSync = wrapSync(params => mightFail(params))

const result = await wrapped(someParams)

if (result.isError()) {

  // True if result holds an error

}

if (result.isOk()) {

  // True if result does not holds an error but holds a value

}

// Throws if result holds an error or returns the value if it contains a value

const value = result.unwrap()

// Returns the value if result holds the value, or the backup value if it holds an error

const altValue = result.unwrapOr('someBackupValue')

// Turns the Result instance into an array

const [error, value] = result.toArray()

if (error) { 

  // handle the error

}

// Destructuring values

const {error,value} = result

const mightBeAnError = someFunction()

// Create a Result instance from a value which might be an error

const result = Result.from(mightBeAnError)

if (result.isError()) {

  // handle error

}

```

### Shortcuts

```javascript

const {ok,err} = require('@fatmatto/resultjs')

// Shortcut for new Result(null,v)

const result = ok(imSureThisIsAGoodValue)

// Shortcut for new Result(error,null)

const result = err(error)

```