How to Localstorage

localstorage-actions.js

const unique_incr = () =>
('' + 1e7 + -1e3 + -4e3 + -8e3 + -1e11).replace(/1|0/g, function() {
        return (0 | (Math.random() * 16)).toString(16)
})
    
const STORAGE_KEY = 'todos';
var fetch = () => JSON.parse(localStorage.getItem(STORAGE_KEY) || '[]')
var save = todos => localStorage.setItem(STORAGE_KEY, JSON.stringify(todos))

var state = { todos: [] }

const todos = state.todos.concat({
   id: unique_incr(),
   done: false,
   editing: false,
   value: "Things to search for"
});

todos
save(todos)
fetch()