Function validateNumber

trivia/code.ts:98–107

(numberString: string)

}

function validateNumber(numberString: string) {
  let number: number;
  if (numberString) {
    number = Number(numberString);
    if (Number.isNaN(number)) {
      return null;
    }
  }
  return number
}

function createAPIUrl(parameters: TriviaParameters): string {
  const { number, category, difficulty, type } = parameters;