Add API to initialize null-initialized properties?

[bigmistqke]

Currently this will fail:

return <Canvas scene={{ background: [1, 0, 0] }} />`

• When encountering an array, the prop handling will try to target[propName].set(...propValue)
• Because Scene.background is null initialized, there is nothing to .set to

The current solution is to pass a THREE.Color instead:

return <Canvas scene={{ background: new Color(1, 0, 0) }} />`

But maybe there could be a way to declare

• if prop[key] exists 👉 prop[key].set(...values)
• if prop[key] exists 👉 prop[key] = new Constructor(...values)

Proposal

Maybe something like:

<Canvas scene={{ background: setOrInit(Color, [1, 0, 0]) }} />

a bit in the vein of https://github.com/tc39/proposal-upsert ?