if i use fetch to iterate an array in javascript code example

Example 1: javascript loop through array

const array1 = ['a', 'b', 'c'];

array1.forEach(element => console.log(element));

Example 2: how to iterate in array of array

var printArray = function(arr) {
    if ( typeof(arr) == "object") {
        for (var i = 0; i < arr.length; i++) {
            printArray(arr[i]);
        }
    }
    else document.write(arr);
}

printArray(parentArray);