SE-0279 introduced multiple trailing closures, making for a simpler way to call a function with several closures.
This will be particularly welcome in SwiftUI, where code like this:
struct OldContentView: View {
@State private var showOptions = false
var body: some View {
Button(action: {
self.showOptions.toggle()
}) {
Image(systemName: "gear")
}
}
}
Can now be written as this:
struct NewContentView: View {
@State private var showOptions = false
var body: some View {
Button {
self.showOptions.toggle()
} label: {
Image(systemName: "gear")
}
}
}
Technically there is no reason why label:
needs to be on the same line as the preceding }
, so you could even write this if you wanted:
struct BadContentView: View {
@State private var showOptions = false
var body: some View {
Button {
self.showOptions.toggle()
}
label: {
Image(systemName: "gear")
}
}
}
However, I would caution against that for readability – a floating piece of code like that is never pleasant, and in Swift it looks like a labeled block rather than a second parameter to the Button
initializer.
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