Swift Hacks: Expert Tips to Write Cleaner and More Efficient Code

Introduction

Swift is a powerful and intuitive programming language for iOS, macOS, watchOS, and tvOS development. To enhance productivity and efficiency, developers use Swift hacks—shortcuts, techniques, and best practices to write cleaner, optimized, and more maintainable code.

In this guide, you'll discover top Swift hacks that can help you improve performance, simplify your code, and boost development speed.

1. Use Guard Statement for Cleaner Code

Instead of deep nesting with if statements, use guard to exit early when conditions are not met.

Example

func validateUser(name: String?) {
    guard let userName = name, !userName.isEmpty else {
        print("Invalid username")
        return
    }
    print("Welcome, \(userName)!")
}

Output

Invalid username

Why it’s a hack?


  • Prevents unnecessary indentation
  • Improves readability
  • Makes code easier to debug

2. Use Lazy Properties to Improve Performance

Swift’s lazy keyword defers property initialization until it's first accessed, optimizing memory usage.

Example

class DataManager {
    lazy var data: [String] = {
        print("Loading data...")
        return ["Swift", "iOS", "Xcode"]
    }()
}

let manager = DataManager()
print("Data not loaded yet")
print(manager.data) // Data loads only when accessed

Output

Data not loaded yet
Loading data...
["Swift", "iOS", "Xcode"]

Why it’s a hack?


  • Saves memory by delaying object creation
  • Speeds up app startup
  • Useful for heavy computations

3. Use map, filter, and reduce Instead of Loops

Higher-order functions can replace loops, making code more expressive and concise.

Example (Using map)

let numbers = [1, 2, 3, 4, 5]
let squaredNumbers = numbers.map { $0 * $0 }
print(squaredNumbers)

Output

[1, 4, 9, 16, 25]

Example (Using filter)

let evenNumbers = numbers.filter { $0 % 2 == 0 }
print(evenNumbers)

Output

[2, 4]

Why it’s a hack?


  • Reduces boilerplate code
  • Increases readability
  • Enhances performance with functional programming

4. Use defer to Ensure Code Execution

Swift's defer ensures that a block of code executes before exiting a scope, regardless of return statements.

Example

func fetchData() {
    defer { print("Closing database connection...") }

    print("Fetching data...")
    return // Defer still executes!
}

fetchData()

Output

Fetching data...
Closing database connection...

Why it’s a hack?


  • Ensures cleanup code always runs
  • Avoids forgetting necessary operations
  • Useful for file handling and memory management

5. Use Property Wrappers for Code Reusability

Property wrappers let you encapsulate logic and reuse it efficiently.

Example

@propertyWrapper
struct Capitalized {
    private var value: String = ""

    var wrappedValue: String {
        get { value }
        set { value = newValue.capitalized }
    }
}

struct User {
    @Capitalized var name: String
}

var user = User(name: "john doe")
print(user.name) // Output: John Doe

Why it’s a hack?


  • Reduces code duplication
  • Simplifies property management
  • Increases maintainability

6. Use Tuples for Multiple Return Values

Instead of creating custom structs, use tuples to return multiple values from a function.

Example

func getUser() -> (name: String, age: Int) {
    return ("Alice", 30)
}

let user = getUser()
print("Name: \(user.name), Age: \(user.age)")

Output

Name: Alice, Age: 30

Why it’s a hack?


  • Avoids unnecessary struct creation
  • Reduces code complexity
  • Easy to use and access

7. Use typealias for Better Readability

typealias simplifies complex types, making code more readable.

Example

typealias CompletionHandler = (Bool, String) -> Void

func fetchData(completion: CompletionHandler) {
    completion(true, "Data fetched successfully")
}

fetchData { success, message in
    print(message)
}

Output

Data fetched successfully

Why it’s a hack?


  • Improves code clarity
  • Shortens function signatures
  • Enhances maintainability

8. Use Default Parameter Values

Reduce redundant method overloads by providing default values.

Example

func greetUser(name: String = "Guest") {
    print("Hello, \(name)!")
}

greetUser() // Output: Hello, Guest!
greetUser(name: "John") // Output: Hello, John!

Why it’s a hack?


  • Avoids writing multiple function overloads
  • Makes function calls flexible
  • Improves code maintainability

9. Use Enums with Associated Values for Complex Data

Enums with associated values allow you to store multiple types in a structured way.

Example

enum APIResponse {
    case success(data: String)
    case failure(error: String)
}

let response = APIResponse.success(data: "User data retrieved")

switch response {
    case .success(let data):
        print("Success: \(data)")
    case .failure(let error):
        print("Error: \(error)")
}

Output

Success: User data retrieved

Why it’s a hack?


  • Reduces the need for multiple structs
  • Improves code organization
  • Enhances error handling

10. Use @discardableResult to Avoid Warnings

Suppress unused return value warnings by marking a function with @discardableResult.

Example

@discardableResult
func increment(_ number: Int) -> Int {
    return number + 1
}

increment(5) // No warning!

Why it’s a hack?


  • Removes unnecessary compiler warnings
  • Makes function calls flexible

11. Use @available to Handle Multiple iOS Versions

Ensure compatibility with older versions of iOS while using the latest features.

@available(iOS 15.0, *)
func newFeature() {
     print("Using new feature in iOS 15 or later")
}

if #available(iOS 15.0, *) {
     newFeature()
} else {
     print("Fallback for older iOS versions")
}

Why it’s a hack?

  • Prevents app crashes on older iOS versions
  • Makes code future-proof
  • Ensures smooth backward compatibility

12. Use compactMap to Remove Nil Values from Arrays

Instead of filtering nil values manually, compactMap does it in one step.

let numbers = ["1", "two", "3", "four"]
let validNumbers = numbers.compactMap { Int($0) }
print(validNumbers)

Output

[1, 3]

Why it’s a hack?

  • Eliminates the need for manual if let checks
  • Cleans up code
  • Improves performance

13. Use Set for Fast Lookups Instead of Arrays

Swift’s Set offers O(1) time complexity for lookups, while Array takes O(n) time.

let numberSet: Set = [1, 2, 3, 4, 5]
print(numberSet.contains(3)) // O(1) lookup

Output

true

Why it’s a hack?

  • Improves performance for large datasets
  • Ideal for fast membership checks
  • Avoids duplicate values automatically

14. Use Result Type for Better Error Handling

Instead of using optionals, use Result for more robust error handling.

enum APIError: Error {
     case notFound
     case unauthorized
}

func fetchData() -> Result {
     return .failure(.notFound)
}

switch fetchData() {
     case .success(let data):
         print("Received data: \(data)")
     case .failure(let error):
         print("Error: \(error)")
}

Output

Error: notFound

Why it’s a hack?

  • Provides stronger error handling than optionals
  • Improves debugging
  • Makes API calls more robust

15. Use where in Loops for Efficient Filtering

Instead of filtering before looping, use where to improve performance.

let numbers = [1, 2, 3, 4, 5, 6]

for num in numbers where num % 2 == 0 {
     print(num)
}

Output

2
4
6

Why it’s a hack?

  • Reduces unnecessary loop iterations
  • Improves performance
  • Makes code more readable

16. Use typealias for Cleaner Code

Simplifies complex types by creating readable aliases.

typealias CompletionHandler = (Bool, String) -> Void

func fetchData(completion: CompletionHandler) {
     completion(true, "Data loaded")
}

fetchData { success, message in
     print(message)
}

Output

Data loaded

Why it’s a hack?

  • Simplifies complex closure signatures
  • Improves code readability