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export type CustomRandomGenerator = (size: number) => Uint8Array | Uint16Array | Uint32Array;
export const customRandom = (random: CustomRandomGenerator, alphabet: string, size: number) => {  const mask = (2 << (Math.log(alphabet.length - 1) / Math.LN2)) - 1;  const step = -~(1.6 * mask * size / alphabet.length);
  return (): string => {    let id = "";    while (true) {      const bytes = random(step);      let i = step;      while (i--) {        // Adding `|| ''` refuses a random byte that exceeds the alphabet size.        id += alphabet[bytes[i] & mask] || '';        if (id.length === +size) return id;      }    }  };}