const { value, signal } = require('realar');
const store = value(0)
const add = store.updater((state, num) => state + num)
const inc = store.updater(state => state + 1)
const addendum = value('0')
const sum = signal()
.map(() => +addendum.val)
.filter()
.to(add);
// Subscribe to store updates
store.to(state => console.log(`state ${state}`));
inc(); // in console: state 1
addendum('9')
sum(); // in console: state 10
addendum('Hi');
sum(); // nothing happens, because the signal has been stopped. It no possible to convert "Hi" string to a number.