Infer associated type on protocol conformance

Using Swift
, ,
4

So the final code becomes:

#if os(iOS) || os(watchOS) || os(tvOS)
import UIKit

public protocol ViewRepresentable: UIViewRepresentable where UIViewType == ViewType {
	associatedtype ViewType
	associatedtype UIViewType = ViewType
	
	@MainActor
	func makeView(context: Context) -> ViewType
	
	@MainActor
	func updateView(_ view: ViewType, context: Context)
}

extension ViewRepresentable {
	@MainActor
	public func makeUIView(context: Context) -> UIViewType {
		makeView(context: context)
	}
	
	@MainActor
	public func updateUIView(_ uiView: UIViewType, context: Context) {
		updateView(uiView, context: context)
	}
}
#elseif os(macOS)
import AppKit

public protocol ViewRepresentable: NSViewRepresentable where NSViewType == ViewType {
	associatedtype ViewType
	associatedtype NSViewType = ViewType
	
	@MainActor
	func makeView(context: Context) -> ViewType
	
	@MainActor
	func updateView(_ view: ViewType, context: Context)
}

extension ViewRepresentable {

	@MainActor
	public func makeNSView(context: Context) -> NSViewType {
		makeView(context: context)
	}
	
	@MainActor
	public func updateNSView(_ nsView: NSViewType, context: Context) {
		updateView(nsView, context: context)
	}
}
#endif

By including where UIViewType == ViewType and where NSViewType == ViewType, I can prevent the user from specifying a different value for NSViewType/UIViewType than ViewType.

Thanks again.