export interface IconProps {
    size?: number;
}

// I use this to create a type that has `size` non-nullable 
// (because it always present due to `defaultProps`
type SafeProps = IconProps & typeof Icon.defaultProps;

export default class Icon extends React.Component<IconProps, any> {
    static defaultProps = {
       size: 10
    };

    render() {
        // cast to SafeProps to safely extract `size`
        const { size } = this.props as SafeProps
        return <div style={{ size }} />
    }
}