The Power of Function Builder: Swift VS SwiftUI

Picture by Arnold Francisca in Unsplash.

Function builders are an incredibly powerful feature that enhance the expressiveness and readability of code in both Swift and SwiftUI. Introduced in Swift 5.4, function builders allow developers to create DSLs (Domain-Specific Languages) and simplify the creation of complex structures using a more concise syntax. In this comprehensive blog post, we will explore the usage and differences of function builders in plain Swift and SwiftUI, providing you with detailed examples and insights. By understanding these differences, you’ll be able to make informed decisions on when and how to leverage each approach in your iOS development projects.

What is a Function Builder?

Function builders, at their core, enable the composition of multiple function calls into a single construct. They are designed to make code more readable and maintainable by providing a declarative and intuitive syntax for building complex data structures. By leveraging custom attributes and result builders, function builders transform a series of function calls into a well-defined structure.

Function Builders in Plain Swift:

In plain Swift, you can use function builders with custom attributes to define your own DSLs. Let’s start by exploring how to define a function builder in plain…