What’s the difference between a function and a closure?
Swift version: 5.0
Closures and functions are very similar in Swift, but there are some subtle differences. When you’re learning, it’s easiest to think of a closure as being a function that doesn’t have a name of its own, and captures any values from its environment.
Nested functions – functions inside other functions – also capture values from their environment, but they have a name. As for global functions – functions that aren’t inside another function or type – they are also like closures, except they have a name and don’t capture values from their environment. Like I said, the differences are subtle!
Helpfully, Swift completely blurs the lines between functions, methods, operators, and closures, allowing us to use them interchangeably as long as they accept and return the correct types of data.
SPONSOR Tired of wasting time debugging your Swift app? Instabug’s SDK is here to help you minimize your debugging time by providing you with complete device details, network logs, and reproduction steps with every bug report. All data is attached automatically. It only takes a line of code to setup. Get started for free.
Available from iOS 8.0
Did this solution work for you? Please pass it on!
Other people are reading…
- Tips for Android developers switching to Swift
- What is an enum?
- How to sum an array of numbers using reduce()
- How to convert an NSRange to a Swift string index
- How to convert a string to a float
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
