BuildOptional and buildEither in Swift

Introduction

BuildOptional and buildEither help you create flexible code blocks that can include optional parts or choose between two options easily.

When you want to include a piece of code only if a condition is true.

When you need to pick one of two possible code paths.

When building user interfaces that may or may not show certain elements.

When handling different cases in a clean and readable way.

Syntax

Swift

func buildOptional(_ component: Component?) -> Component?
func buildEither(first component: Component) -> Component
func buildEither(second component: Component) -> Component

buildOptional wraps an optional component, allowing you to include or skip it.

buildEither lets you choose between two components, marking one as first or second.

Examples

This example shows how buildOptional returns the string if it exists or nil if it doesn't.

Swift

func buildOptional(_ component: String?) -> String? {
    return component
}

let optionalText = buildOptional("Hello" as String?)
let noText = buildOptional(nil)

This example shows how buildEither picks between two options, labeling them as first or second.

Swift

func buildEither(first component: String) -> String {
    return "First: \(component)"
}

func buildEither(second component: String) -> String {
    return "Second: \(component)"
}

let firstChoice = buildEither(first: "Option A")
let secondChoice = buildEither(second: "Option B")

Sample Program

This program shows how buildOptional returns a value or nil, and how buildEither picks between two choices.

Swift

import Foundation

// Simulate buildOptional
func buildOptional(_ component: String?) -> String? {
    return component
}

// Simulate buildEither
func buildEither(first component: String) -> String {
    return "First choice: \(component)"
}

func buildEither(second component: String) -> String {
    return "Second choice: \(component)"
}

// Using buildOptional
let optionalGreeting = buildOptional("Hello, friend!" as String?)
let noGreeting = buildOptional(nil)

// Using buildEither
let choice1 = buildEither(first: "Coffee")
let choice2 = buildEither(second: "Tea")

print(optionalGreeting ?? "No greeting")
print(noGreeting ?? "No greeting")
print(choice1)
print(choice2)

Important Notes

buildOptional helps you include code only if it exists, like showing a message if available.

buildEither is useful for choosing between two paths, like picking one option in a menu.

These functions are often used in Swift's result builders to make code cleaner and easier to read.

Summary

buildOptional wraps optional parts of code to include or skip them.

buildEither chooses between two code options, marking one as first or second.

They help write flexible and readable Swift code, especially in UI building.