Thread by @davedelong

A handy Swift convenience thing I came up with recently (1/n):

struct Backport<Content> {
let content: Content
}

extension View {
var backport: Backport<Self> { Backport(content: self) }
}

extension Backport where Content: View {
@ViewBuilder func badge(_ count: Int) -> some View {
if #available(iOS 15, *) {
content.badge(count)
} else {
// some fallback?
content
}
}
}

Advantages:
- keep all version-specific checks in a single file
- use the same method name on all os versions
- Backport<T> isn't a view; forgetting the method = helpful compiler error
- basically a namespace for compatibility shims
- easy to ID usage: search for ".backport"

You can use this for other things too, by doing:

extension Backport where Content: UIViewController { … }

etc

When you up your minimum SDK version, go through the relevant usage sites and delete ".backport" and that's it. 🎉

This works especially well for methods and modifiers; less when when you want to backport an entirely new *type*, although you can make it work:

extension Backport<View> {
struct AsyncImage: View { … }
}