Quick Answer

Different function patterns in JavaScript.

Understanding the Issue

JavaScript functions are first-class objects with several declaration styles.

The Problem

This code demonstrates the issue:

Javascript Error 
// Need to implement functionality

The Solution

Here's the corrected code:

Javascript Fixed 
// Function declaration (hoisted)
function add(a, b) {
    return a + b;
}

// Function expression
const multiply = function(a, b) {
    return a * b;
};

// Arrow function (ES6)
const divide = (a, b) => a / b;

// Default parameters
function greet(name = "Guest") {
    return `Hello ${name}`;
}

// Rest parameters
function sum(...numbers) {
    return numbers.reduce((total, num) => total + num, 0);
}

Key Takeaways

Use arrow functions for conciseness and declarations for hoisting.