Validate credit/debit card number (Luhn Algorithm)

validateCard.js

export const validateCard = ((arr) => {
  return (num) => {
    let len = num.length;
    let bit = 1;
    let sum = 0;
    let val;
    while (len) {
      val = parseInt(num.charAt(--len), 10);
      // eslint-disable-next-line no-bitwise,no-cond-assign
      sum += (bit ^= 1) ? arr[val] : val;
    }
    return sum && sum % 10 === 0;
  };
})([0, 2, 4, 6, 8, 1, 3, 5, 7, 9]);