Conditional Rendering

Conditional rendering is usually introduced early in React applications, though not in our working example. It happens when you decide to render either of two elements, which sometimes is a choice between rendering an element or nothing. The simplest usage of a conditional rendering can be expressed by an if-else statement in JSX.

The result object in the local component state is null in the beginning. So far, the App component returned no elements when the result hasn’t arrived ...