Is there a way to declare an object property without initializing it?

^{A.S.: Object property order in JS is a very complicated topic. For my intents and purposes, only insertion order matters.}

TL;DR: Is there a way to declare an object property without giving it a value?

const user = { name: unset, age: 42 }

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I have a set of asynchronous functions, each returning a value associated with a unique key. They are then invoked in parallel to construct an object with key-value pairs used as entries (properties). Something like this:

const props = {}
const propsSet = getters.map(async ([key, getValue]) => {
  props[key] = async getValue()
})

await Promise.all(propsSet)

return props

Try it.

Sine all of this is asynchronous, the order of properties in props is all over the place: I get sometimes { foo: …, bar: … }, sometimes { bar: …, foo: … }. I could fix that by associating each getter with a sequence number. But a much easier solution is to just initiate the properties as soon as possible; due to how event loop works, this is basically a guarantee that properties of props will be ordered the same as in getters:

const propsSet = getters.map(async ([key, getValue]) => {
    props[key] = null // or any other initialization token
    props[key] = await getValue()
})

In pure JS this a perfectly normal thing to do, but in TS this is usually a compiler error (since arbitrary “initialization token” isn’t assignable to strictly typed properties of props); so, I have to do shush the compiler, which I don’t like to do:

// @ts-expect-error
values[key] = null

Try it.

I’ve realized that what I basically need is very similar to declaring variables separately from initializing them, – like in old-school JS style:

var value1, value2

value1 = 42
value2 = 17

Is there any existing or upcoming (proposal) way of declaring object properties without initializing them?

Note that I’m not asking about ways of ordering properties. There are many strategies to do that, including usage of the aforementioned sequence numbers (e.g., array indexes).