immutable-list-reduce-async

Small extention to the immutable list to perform an async reducer

This can be useful if a reducer function has to perform an asynchronous operation. So, instead of a result it returns an instance of a Task (from data.task package):

// myReducer :: b -> a -> Task b
const myReducer = (acc, el) =>
  new Task((reject, resolve) => {
    // Some async action here.
    setTimeout(function () {
      resolve(acc + el)
    }, 0)
  })
 
// reduceAsync :: (b -> a -> Task b) -> b -> Task b
List.prototype.reduceAsync

Example:

const Task = require('data.task')
const { List } = require('./index')
 
// Reduce to the sum of list elements with an async action (Task):
var app = List([1, 2, 3]).reduceAsync((acc, x) => Task.of(acc + x), 0)
 
app.fork(err => console.log(err),
         res => console.log(res))
 
// >>> 6