Golang style error handling for Functions, Promises and Thenables.
npm install noexGolang style error handling for Functions, Promises and Thenables.
Using npm:
``sh`
$ npm install noex
Using yarn:
`sh`
$ yarn add noex
js
// ESM
import { noex } from 'noex'
`
`js
// CJS
const { noex } = require('noex')
`Resolve a Promise:
`js
// as a "tuple"
const [ file, fileError ] = await noex(fs.promises.readFile('someFile'))
// as a "named tuple"
const { value, error } = await noex(fs.promises.readFile('someFile'))
`Call a Function:
`js
// as a "tuple"
const [ json, jsonError ] = noex(() => JSON.parse('{"success": true}'))
// as a "named tuple"
const { value, error } = noex(() => JSON.parse('{"success": true}'))
`Example
`js
router.get('/api/resource/:id', async (req, res) => {
const [ resource, resourceErr ] = await noex(
resourceService.findById(req.params.id)
) // database error
if (resourceErr) {
logger.error(resourceErr)
return res.sendStatus(500)
}
// resource not found
if (! resource) {
return res.sendStatus(404)
}
return res.json(resource)
})
`API
#### noex(predicate: Promise): Promise<Result >
Run a function in a try-catch block and return the result.
`js
const [ content, error ] = await noex(
fs.promises.readFile('path/to/file')
)
`#### noex(predicate:
Function): Result
Run a promise or thenable in a try-catch block and return the result.
`js
const [ json, error ] = noex(function () {
return JSON.parse('{ "identity": "Bourne" }')
})
`#### noex(predicate:
Array): PromiseResult>>
Run a series of functions, promises and/or thenables and return their results.`js
const [ res1, res2 ] = await noex([
() => JSON.parse('{ "identity": "Bourne" }'),
fs.promises.readFile('path/to/file')
])
`#### noex.wrap(fn:
(...args: any[]) => Promise): (...args: any[]) => Promise<Result >
Wrap a function that returns a promise with noex.
`js
const readFile = noex.wrap(function (file) {
return fs.promises.readFile(file)
})const [ content, error ] = await readfile('path/to/file')
`
#### noex.wrap(fn: (...args: any[]) => any): (...args: any[]) => Result
Wrap a function with noex.
`js
const parseJson = noex.wrap(JSON.parse)const [ json, error ] = parseJson('{ "identity": "Bourne" }')
`#### noex.chain(predicates: Array<(...args: any[]) => any>): Promise<Result >
Run the given predicates in sequence, passing the result of each predicate to the next one in the list.
`js
const [ val, err ] = await noex([
() => JSON.parse('{ "identity": "Bourne" }'),
json => json.identity.toUpperCase(),
])
console.log(val) //=> "BOURNE"
`#### Result:
Array
The object to hold the resulting value or error of a function, promise or thenable.Properties:
* value (
any) : The resulting value of a function, promise or thenable.
* val (any) : Same as value.
* error (Error) : The error caught by the try-catch block.
* err (Error`) : Same as error.This project is open-sourced software licensed under the MIT license.