Cycle.js with reducer-like events

cycle-with-reducers.js

const Cycle = require('@cycle/core');
const {makeDOMDriver, div, button} = require('@cycle/dom');
const {Observable} = require('rx');

function intent({ DOM }) {
  const incr$ = DOM
    .select('.incr')
    .events('click')
    .map(() => prev => prev + 1);
    
  const decr$ = DOM
    .select('.decr')
    .events('click')
    .map(() => prev => prev - 1);
    
  const reset$ = DOM
    .select('.reset')
    .events('click')
    .map(() => () => 0);
    
  return { incr$, decr$, reset$ };
}

function model({ incr$, decr$, reset$ }) {
  const count$ = incr$
    .merge(decr$)
    .merge(reset$)
    .startWith(0)
    .scan((prev, change) => change(prev));
    
  return { count$ };
}

function view({ count$ }) {
  const DOM = count$.map(count =>
    div('.counter', [
      'Count: ' + count,
      button('.incr', '+'),
      button('.decr', '-'),
      button('.reset', 'Reset')
    ])
  );
  
  return { DOM };
}

const main = sources => view(model(intent(sources)))

const sources = {
  DOM: makeDOMDriver('#app')
}

Cycle.run(main, sources);