untitled notebook

class Item { constructor(itemNumber){ this.itemNumber = itemNumber; } toString(){ return "Item #" + this.itemNumber; } } function myFilter(element, index, array){ return element.item.itemNumber > 3; } function myFormatter(element, index, array){ return {index, item: element, output: element.toString()}; } var listOfObjects = []; listOfObjects.push(new Item(5)); listOfObjects.push(new Item(4)); listOfObjects.push(new Item(1)); listOfObjects.push(new Item(8)); // var output = formatArray(listOfObjects, myFilter, myFormatter); const output = listOfObjects .map(myFormatter) .filter(myFilter) .map(e => `${e.index} ${e.output}`) .join("\n"); console.log(output);