Collections

async/await-ready array methods for Node.js

Installation · Docs · Usage

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The @supercharge/collections package provides a convenient wrapper to work with arrays.

npm i @supercharge/collections

Find all the details and available methods in the extensive Supercharge docs.

The package exports a function accepting an array as a parameter. From there, you can chain all collection methods.

A created collection (Collect([1, 2, 3])) is synchronous by default. That means it behaves like JavaScript’s array methods.

In contrast to JavaScript’s array methods, collections have a lot more methods available making your code a lot simpler. Here are basic examples using a collection:

const User = require('../models/user')
const Collect = require('@supercharge/collections')

const users = await User.findAll()

const notSubscribedUsers = Collect(users)
  .filter(user => {
    return user.notSubscribedToNewsletter
  })
  .all()

// notSubscribedUsers = [ <list of not-yet-subscribed users> ]

Here’s another example outlining how to determine whether the array “has” an item:

// “has” in JS Arrays
const hasNotSubscribedUsers = !![].concat(users).find(user => {
  return user.notSubscribedToNewsletter
})

// “has” in Collections
const hasNotSubscribedUsers = Collect(users).has(user => {
  return user.notSubscribedToNewsletter
})

All available methods are outlined in the docs.

The package is async/await-ready and supports async callback functions. A collection becomes async (returns a promise) as soon as you provide an async callback method to methods like map, filter, find, and so on. You then need to await the collection pipeline:

const User = require('../models/user')
const Collect = require('@supercharge/collections')

const users = await User.findAll()

const subscribedUsers = await Collect(users)
  .filter(user => {
    return user.notSubscribedToNewsletter
  })
  .map(async user => { // <-- providing an async callback creates an async collection that you need to `await`
    await user.subscribeToNewsletter()

    return user
  })

// subscribedUsers = [ <list of newly-subscribed users> ]

You can directly await async collections without ending the call chain with .all(). You can still call .all() though, it works as well.

Do you miss a collection function? We very much appreciate your contribution! Please send in a pull request 😊

1. Create a fork
2. Create your feature branch: git checkout -b my-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request 🚀

MIT © Supercharge

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