I like how the if proposal is down voted, probably because it's mentioning Angular. Conditional rendering in React is not always very clean. Most codebases end up resorting with something similar to this in a container to show a spinner while data is loading and rendering it when done.
Problem is that the inner component will still be parsed and fail with cannot read property person of undefined. Yes, you can do this with a simple condition in your render function, but then it's not declarative any more.
<ConditionalSpinner renderIf={data}><PersonRenderer person={data.person} /></ConditionalSpinner>
Problem is that the inner component will still be parsed and fail with cannot read property person of undefined. Yes, you can do this with a simple condition in your render function, but then it's not declarative any more.