This article has been archived, as it was published several years ago, so some of its information might now be outdated. For more recent articles, please visit the main article feed.
Using closure types in generic constraints
Discover page available: GenericsYou can use closure types in generic constraints in Swift. Enables nice APIs for handling sequences of closures.
extension Sequence where Element == () -> Void {
func callAll() {
forEach { $0() }
}
}
extension Sequence where Element == () -> String {
func joinedResults(separator: String) -> String {
return map { $0() }.joined(separator: separator)
}
}
callbacks.callAll()
let names = nameProviders.joinedResults(separator: ", ")
Swift by Sundell is brought to you by the Genius Scan SDK — Add a powerful document scanner to any mobile app, and turn scans into high-quality PDFs with one line of code. Try it today.