DataStore with Rx and Ramda

gistfile1.js

var initialData = []

// These can be converted from other events
var add_ = new Rx.Subject()
var remove_ = new Rx.Subject()

var addF_ = add_.map(R.unary(R.curry(R.union)))
var removeF_ = remove_.map(R.unary(R.flip(R.difference)))

var update = (data, updateF) => updateF(data)

var data_ = addF_.merge(removeF_).scan(initialData, update).shareValue(initialData)

data_.subscribe(data => console.log(data))

add_.onNext([1,2,3,4,5])
// [1,2,3,4,5]

remove_.onNext([3,4,5])
// [1,2]