Package Exports

untry
untry/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (untry) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

Untry

Better error handling in JavaScript

This library provides a simple way to handle errors in JavaScript, inspired by the error handling philosophy in Go.

Installation

npm

npm install untry

yarn

yarn add untry

Usage

untry executes a function and return an array with the resulting value in the first place, and the thrown error in the second one.

import untry from 'untry'

let [value, error] = untry(() => someFunc())

// async
let [value, error] = await untry(() => someFunc())

Defer

Defer executes the passed functions if any error is thrown inside the untry execution.

let [value, error] = untry((defer) => {
  defer(error => {
    // execute if any error
  })

  // function code
  return someFunc()
})

Example:

import fs from 'node:fs/promises'

let [value, error] = untry((defer) => {
  let filehandle

  // close file handler if something unexpected happens
  defer(error => {
    console.log(error)
    if (filehandle) filehandle.close()
  })

  filehandle = await fs.open('/Users/joe/test.txt', 'r')
  return filehandle.readFile({ encoding: 'utf8' })
})

Utilities

error(err: Error, name: string): CustomError

Returns a serializable custom Error

const err = untry.error(new Error('Bad token!'), 'TOKEN_ERROR')

console.log(JSON.stringify(err))

/*
Console output

{
  '@untry/error': true,
  'name': 'TOKEN_ERROR',
  'message': 'Bad token!'
}
*/

Contributing

Contributions are welcome! Please submit a pull request or issue on GitHub.

untry