An interesting react typescript destructuring syntax, kebab naming property with a default value

less than 1 minute read

type ComponentProps = React.HTMLProps<HTMLDivElement>;

export default function Component({
  "aria-busy": ariaBusy = true,
}: ComponentProps) {
  return (
    <div ariaBusy={ariaBusy}>
      <h1>Interesting react typescript destructuring syntax</h1>
    </div>
  );
}

First glance at the code above, you could get confused with the syntax { "aria-busy": ariaBusy = true } where the component trying to destructure props passed from parent components.

Here is the explain:

  1. if props has a property name using kebab style, e.g. “aria-busy”, the syntax to destructure it is to use quotes to wrap the property: { "aria-busy": ariaBusy }, because without the quotes, ts/js interpreter would believe the dash ‘-‘ is a subtraction operator, and wouldn’t understand the way it’s used.

  2. setting a default value for destructured property is supported in ts/js, the syntax to do it is just to put a default value like = true at right side of the variable.

In a nutshell, { "aria-busy": ariaBusy = true } is a valid destructuring syntax supported by modern ts/js.