Similar to as javascript array.

But you would need to specify the types of the parameters and also a return type. Yes you could configure your setup to not care about these things, but then that would defeat the object of using typescript.

export function shuffle<T>(array: T[]): T[] {
    let currentIndex = array.length,  randomIndex;

    // While there remain elements to shuffle.
    while (currentIndex != 0) {
  
      // Pick a remaining element.
      randomIndex = Math.floor(Math.random() * currentIndex);
      currentIndex--;
  
      // And swap it with the current element.
      [array[currentIndex], array[randomIndex]] = [
        array[randomIndex], array[currentIndex]];
    }
  
    return array;
};

You can get different options of shuffle from this question.