Platform-specific modifier application

PlatformSpecific.swift

import SwiftUI

struct Platform: OptionSet
{
	let rawValue: Int
	
	static let iOS = Platform(rawValue: 1<<0)
	static let tvOS = Platform(rawValue: 1<<1)
	static let watchOS = Platform(rawValue: 1<<2)
	
	static var current: Platform
	{
		var tmp: Platform = []
		
		#if os(iOS)
		tmp.insert(.iOS)
		#endif
		
		#if os(watchOS)
		tmp.insert(.watchOS)
		#endif
		
		#if os(tvOS)
		tmp.insert(.tvOS)
		#endif
		
		return tmp
	}
}


struct PlatformSpecificModifier<M: ViewModifier>: ViewModifier
{
	let platform: Platform
	let modifier: M
	
	@ViewBuilder
	func body(content: Content) -> some View
	{
		if Platform.current.intersection(platform) != []
		{
			content.modifier(modifier)
		}
		else
		{
			content
		}
	}
}

extension View
{
	func platformSpecific<M: ViewModifier>(_ platform: Platform, modifier: M) -> some View
	{
		self.modifier(PlatformSpecificModifier(platform: platform, modifier: modifier))
	}
	
	@ViewBuilder
	func onlyOn<V: View>(_ platform: Platform, modified: (View)->V) -> some View
	{
		if Platform.current.intersection(platform) != []
		{
			modified(self)
		}
		else
		{
			self
		}
	}
}