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# Question 36

### Question

How would you use default parameters with rest parameters in JavaScript?

### Answer

Here's how to use default parameters and rest parameters together in JavaScript:

```javascript
function greet(name = "World", ...greetings) {
  console.log(`Hello ${name}!`); 
  for (const greeting of greetings) {
    console.log(`${greeting}`);
  }
}

greet(); // Output: Hello World!

greet("Alice", "Nice to meet you", "How are you?"); // Output: Hello Alice!
                                            //          Nice to meet you
                                            //          How are you?

greet("Bob", "Hi there");                      // Output: Hello Bob!
                                            //          Hi there
```

**Explanation:**

1. **Default Parameters:** The `name = "World"` part sets a default value for the `name` parameter if no argument is provided.
2. **Rest Parameter:** The `...greetings` syntax creates a rest parameter. This allows the function to accept any number of additional arguments, which are collected into an array called `greetings`.
3. **Function Execution:**
   * When you call `greet()` without arguments, it uses the default "World" for `name` and prints nothing else (because no greetings were provided).
   * When you provide specific values for both `name` and `greetings`, they are used as expected.

**Key Points:**

* Default parameters come *before* rest parameters in the function declaration.
* Rest parameters must be the last parameter in a function definition.