How to Write Closures

Steps

1. Paste the code into a Swift file or playground.
2. Run it once to verify the output.
3. Adjust the inputs to match your use case.

Copy and paste

import Foundation

let numbers = [1, 2, 3, 4]
let doubled = numbers.map { value in
    value * 2
}

print(doubled)

Notes

• Keep functions small and focused for reuse.
• Prefer safe APIs like optionals and guards.