🎯 What is a Closure?

A closure is a small block of code that you can pass around and execute later. It’s like a mini-function that you can save, hand over, and call whenever you need it!

☕ Imagine Ordering at a Cafe

Imagine you go to a cafe and order “A Latte, please!” That order is like a closure — you are giving instructions to the barista (the Swift function) about what you want them to do later.

Swift Code Example

func makeDrink(order: (String) -> Void) {
    order("Latte")
}

makeDrink { drinkName in
    print("Making a \(drinkName)!")
}

Result ➡️ Making a Latte! will be printed.

🧠 Why Do We Need a Variable Name (like drinkName)?

Inside a closure, you need a variable to catch the value that Swift sends (like “Latte”). Here, drinkName is that catcher!

🤔 Why Are Closures Needed in Swift?

Closures are super useful in Swift because they allow you to:

• Run code later (like when a button is tapped)
• Customize actions for each item (like showing different list items)
• Handle results when a network request finishes

“Whenever you need to choose the timing and behavior flexibly, closures are the answer!”

💻 Real Swift Usage Example

Closure When a Button is Pressed

import SwiftUI

struct ContentView: View {
    var body: some View {
        Button("Tap Me") {
            print("Button was tapped!")
        }
    }
}

Here, we pass a closure to Button that defines “what to do when tapped”. This is a very real use of closures!

📦 Quick Flow Summary

• Function makeDrink accepts a closure
• It calls order("Latte") inside
• The closure catches “Latte” into drinkName
• Prints “Making a Latte!”