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Javascript: update an object from its method without this keyword

I am working with a library which implement a class Graph that have a method Graph.registerNode()
The methode has the following signature.
Graph.registerNode('node-name', {
object: {
options: {
key: "value"
},
updateOption: () => {
this.options = { key: "other value" }
}
})
Is it possible to update the options key from updateOptions without using the this keyword?

const options = {
key: "value"
};
Graph.registerNode('node-name', {
object: {
options,
}
updateOption: () => {
options.key = "other value";
}
})
How about this?

I was able to solve this via a factory function
const factoryFunction = () => {
let options: {
key: "value"
}
return Object.freeze({
updateOption: () => {
options = {
key: 'updated value',
}
},
printOption: () => {
console.log(options)
}
})
}
const config = factoryFunction()
Graph.registerNode('node-name', config)

is there a way to use strings with some object's property in javascript? [duplicate]

This question already has answers here:
Accessing an object property with a dynamically-computed name
(19 answers)
Closed last year.
it's hard to explain, bur lets go on with a example
const exampleProperty = {
log1: () => {
console.log('log1')
},
log2: () => {
console.log('log2')
},
log3: () => {
console.log('log3')
},
log4: () => {
console.log('log4')
}
}
for (let i = 0; i < 4; i++) {
// now here I want to run all the functions in the example Property
// I imagined it something like
exampleProperty.log${i}
// but this is invalid syntax
}
There might be a real easy answer to this but as I am new i really can't imagine what to do

If you wanted to enumerate every method
const exampleProperty = {
log1: () => {
console.log('log1')
},
log2: () => {
console.log('log2')
},
log3: () => {
console.log('log3')
},
log4: () => {
console.log('log4')
}
}
Object.values(exampleProperty).forEach(p => p())

Working example, using backticks
const exampleProperty = {
log1: () => {
console.log('log1')
},
log2: () => {
console.log('log2')
},
log3: () => {
console.log('log3')
},
log4: () => {
console.log('log4')
}
}
for (let i = 1; i <= 4; i++) {
// now here I want to run all the functions in the example Property
// I imagined it something like
exampleProperty[`log${i}`]();
// but this is invalid syntax
}

Why at others versions writing code function is and is't a constructor?

I have a object with function
{
ready(_callback) {
_callback();
},
Map() {
this.geoObjects = () => {
return {
add() {},
get() {
return {
removeAll() {},
add() {},
};
},
}
};
this.setCenter = () => {};
this.setZoom = () => {};
},
},
an then I write
Map: function () { // it is a constructor
Map() { // it is not a constructor
Map: () => { //it is not a constructor
Why? Help pls. And how to write this object with a constructor function on ES6 format?

How to add a function to Object's named property with correct context in javascript

I have a working piece of code as below:
let pageParams = {
data: { todos: [], desc: '' }
}
pageParams.onLoad = function () {
//I am trying to encapsulate this to a standalone function and
// make it generic, instead of hard coding the 'this.addTodo=XXX'
const evProducer = {
start: listener => {
//Here, I am adding a named property function
this.addTodo = ev => {
listener.next(ev.detail.value)
}
},
stop: ()=>{}
}
const input$ = xs.create(evProducer)
input$.compose(debounce(400)).subscribe({
next: val => console.log(val)
})
}
The code works and now I am going to do some refactor work, i.e. move the logic out of this onLoad function. So I move the logic to another module
let xsCreator = {}
xsCreator.fromEvent = function(handler){
const evProducer = {
start: listener => {
handler = ev => listener.next(ev.detail.value)
},
stop: () => {}
}
return xs.create(evProducer)
}
And in the previous onLoad function becomes the following:
pageParams.onLoad = function () {
xs.fromEvent(this.addTodo).subscribe(blablabla)
}
but it does not work. I guess I might use apply/call/bind to make this work, but don't know how to. Anyone can help? Thanks in advance

I've found the solution, I should use Object.defineProperty to add a named property for object.
xsCreator.fromInputEvent = (srcObj, propertyName) => {
const evProducer = {
start: (listener) => {
Object.defineProperty(
srcObj,
propertyName,
{value: ev => listener.next(ev.detail.value)})
},
stop: () => {}
}
return xs.create(evProducer)
}

javascript calling parent method from child

I have the following object:
var party =
{
food:
{
serve: function () {
// I want to call turnOff method from here
}
cleanUp: function () {
}
}
music:
{
turnOff: function () {
}
}
}
So as the comment points out, I want to call the turnOff method from the music object, how can I do this? this refers to the food object but I need to access the music object...

var party =
{
food:
{
serve: function () {
party.music.turnOff();
},
cleanUp: function () {
}
},
music:
{
turnOff: function () {
}
}
}

Use a constructor instead of a literal with a variable referencing the parent object
var party = new (function()
{
var self = this;
this.food =
{
serve: function () {
self.music.turnoff();
},
cleanUp: function () {
}
}
this.music =
{
turnOff: function () {
}
}
})();

Call it as party.music.turnOff().
FYI, your above code block isn't valid. You're missing some commas - after the serve and food closing braces.