Functional Reactive Programming with Bacon.js
Junction 22.9.2015
Olli Mahlamäki / Reaktor
Agenda
- What?
- Why?
- Why not?
What?
Bacon.js
Javascript FRP library
- github.com/baconjs/bacon.js
- Created by Juha Paananen (Reaktor)
Functional programming
FP
var messages = [
{ from: "olli", to: "fernando", text: "Hi Ferkku" },
{ from: "fernando", to: "olli", text: "What's up?" },
{ from: "olli", to: "fernando", text: "Giving a presentation to Aalto ES" },
{ from: "fernando", to: "olli", text: "Ok cool" },
]
messages
.filter(function(message) { return isDirectedToMe(message) })
.map(function(message) { return message.text })
.forEach(show)
FRP (with bacon)
var messages = [
{ from: "olli", to: "fernando", text: "Hi Ferkku" },
{ from: "fernando", to: "olli", text: "What's up?" },
{ from: "olli", to: "fernando", text: "Giving a presentation to Aalto ES" },
{ from: "fernando", to: "olli", text: "Ok cool" },
]
// Simulate messages coming from server
var messagesE = Bacon.sequentially(1000, messages)
messagesE
.filter(function(message) { return isDirectedToMe(message) })
.map(function(message) { return message.text })
.forEach(show)
Bacon vs. Promises
- Both solve async cases
- Promise: 0-1 values
- EventStream: 0-n values
- Combo: Bacon.fromPromise(...)
Why?
Why
- Async problems are hard
- Almost every modern web app is async
- Tools from FP to async problems
Bacon.js ready for production
Bacon <3 React
Why not?
Why not?
- Tough learning curve
- Discipline needed for architecture