I am wondering why I'm getting this error message? But array.map is correct in how I'm stating it?
/home/ccuser/workspace/credit-card-checker/main.js:40 newArr = array.map((element, index) => index % 2 === 1 ? element * 2 : element); ^
TypeError: array.map is not a function at validateCred
const valid1 = [4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8];
const validateCred = (array) => {
let newArr = [];
let newestArr = [];
let reducedResult = 0;
const reducer = (previousValue, currentValue) => previousValue + currentValue;
if (array.length % 2 === 0) {
newArr = array.map((element, index) => index % 2 === 0 ? element * 2 : element);
} else {
newArr = array.map((element, index) => index % 2 === 1 ? element * 2 : element);
}
newestArr = newArr.map((element) => element > 9 ? element - 9 : element);
let sum = newestArr.reduce((prev, curr) => prev += curr);
return sum % 10 === 0
};
const findInvalidCards = (nestedArray) => {
let invalidArray = [];
invalidArray = nestedArray.forEach((element) => validateCred(element) === false);
return invalidArray;
};
findInvalidCards(valid1);valid1 is supposed to be an array of arrays, so here I just wrap another set of square brackets.
Also, forEach always returns undefined, so I changed it to use map instead.
const valid1 = [[4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8]];
const validateCred = (array) => {
let newArr = [];
let newestArr = [];
let reducedResult = 0;
const reducer = (previousValue, currentValue) => previousValue + currentValue;
if (array.length % 2 === 0) {
newArr = array.map((element, index) => index % 2 === 0 ? element * 2 : element);
} else {
newArr = array.map((element, index) => index % 2 === 1 ? element * 2 : element);
}
newestArr = newArr.map((element) => element > 9 ? element - 9 : element);
let sum = newestArr.reduce((prev, curr) => prev += curr);
return sum % 10 === 0
};
const findInvalidCards = (nestedArray) => {
let invalidArray = [];
invalidArray = nestedArray.map((element) => ({cardNumber: element.join(""), isValid: validateCred(element)}));
return invalidArray;
};
console.log(findInvalidCards(valid1));