davidfowl/Example1.cs

## _Platform.cs
using System;

namespace Analogy
{
    // Each interface represents a target framework and methods represents groups of APIs available on that target framework.
    // The goal is to show the relationship between .NET Standard API surface and other .NET platforms


    // .NET Standard

    interface INetStandard10
    {
        void Primitives();
        void Reflection();
        void Tasks();
        void Collections();
        void Linq();
    }

    interface INetStandard11 : INetStandard10
    {
        void ConcurrentCollections();
        void InteropServices();
    }

    interface INetStandard12 : INetStandard11
    {
        void ThreadingTimer();
    }

    interface INetStandard13 : INetStandard12
    {
        void FileSystem();
        void Console();
        void ThreadPool();
        void Process();
        void Sockets();

        void AsyncLocal();
    }

    interface INetStandard14 : INetStandard13
    {
        void IsolatedStorage();
    }

    interface INetStandard15 : INetStandard14
    {
        void AssemblyLoadContext();
    }

    // .NET Framework

    interface INetFramework45 : INetStandard11
    {
        void FileSystem();
        void Console();
        void ThreadPool();
        void Crypto();
        void WebSockets();
        void Process();
        void Sockets();

        void AppDomain();
        void Xml();
        void Drawing();
        void SystemWeb();
        void WPF();
        void WindowsForms();
        void WCF();
    }

    interface INetFramework451 : INetFramework45, INetStandard12
    {
        // TODO: .NET Framework 4.5.1 specific APIs
    }

    interface INetFramework452 : INetFramework451, INetStandard12
    {
        // TODO: .NET Framework 4.5.2 specific APIs
    }

    interface INetFramework46 : INetFramework452, INetStandard13
    {
        // TODO: .NET Framework 4.6 specific APIs
    }

    interface INetFramework461 : INetFramework46, INetStandard14
    {
        // TODO: .NET Framework 4.6.1 specific APIs
    }

    interface INetFramework462 : INetFramework461, INetStandard15
    {
        // TODO: .NET Framework 4.6 specific APIs
    }

    // Mono

    interface IMono43 : INetFramework46
    {
        void MonoSpecificApi();
    }

    // Windows Universal Platform

    interface IWindowsUniversalPlatform : INetStandard14
    {
        void GPS();
        void Xaml();
    }

    // Xamarin

    interface IXamarinIOS : INetStandard15
    {
        void AppleAPIs();
    }

    interface IXamarinAndroid : INetStandard15
    {
        void GoogleAPIs();
    }

    // .NET Core

    interface INetCoreApp10 : INetStandard15
    {

    }

    // Future platform

    interface ISomeFuturePlatform : INetStandard13
    {
        // A future platform chooses to implement a specific .NET Standard version.
        // All libraries that target that version are instantly compatible with this new
        // platform
    }
}

## Example1.cs
namespace Analogy
{
    /// <summary>
    /// This example shows that a library that needs access to target .NET Standard 1.3
    /// can only access APIs available in that .NET Standard. Even though similar the APIs exist on .NET
    /// Framework 4.5, it implements a version of .NET Standard that isn't compatible with the library.
    /// </summary>INetCoreApp10
    class Example1
    {
        public void Net45Application(INetFramework45 platform)
        {
            // .NET Framework 4.5 has access to all .NET Framework APIs
            platform.FileSystem();

            platform.Console();


            // This fails because .NET Framework 4.5 does not implement .NET Standard 1.3
            // Argument 1: cannot convert from 'Analogy.INetFramework45' to 'Analogy.INetStandard13'
            NetStandardLibrary13(platform);
        }

        public void NetStandardLibrary13(INetStandard13 platform)
        {
            platform.FileSystem();

            platform.Console();
        }
    }


    /// <summary>
    /// This example shows a library targeting multiple frameworks and 2 different applications
    /// using that library. MultipleTargetsLibrary needs access to the FileSystem, that API was only available
    /// in .NET Standard 1.3. .NET Standard 1.3 only works with .NET Framework 4.6. Because of this
    /// MultipleTargetsLibrary needs to add support for .NET Framework 4.5 explicitly.
    /// </summary>
    class Example2
    {
        public void Net45Application(INetFramework451 platform)
        {
            // On the .NET 4.5.1 application, the INetFramework45 implementation is choson
            MultipleTargetsLibrary(platform);
        }

        public void NetCoreApplication(INetCoreApp10 platform)
        {
            // On the .NET Core 1.0 application, the INetStandard13 implementation is choson
            MultipleTargetsLibrary(platform);
        }

        public void MultipleTargetsLibrary(INetFramework45 platform)
        {
            platform.FileSystem();
        }

        public void MultipleTargetsLibrary(INetStandard13 platform)
        {
            platform.FileSystem();
        }
    }

    /// <summary>
    /// This example shows how future platforms can be added without the need to change libraries that
    /// target the .NET Standard. JSON.NET targets .NET Standard 1.0 and can run on *ANY* platform that implements
    /// the standard.
    /// </summary>
    class Example3
    {
        /// <summary>
        /// This future platform implements .NET Standard 1.3
        /// </summary>
        public void FuturePlatformApplication(ISomeFuturePlatform platform)
        {
            // You are able to use JSON.NET with the future platform without recompiling JSON.NET
            JsonNet(platform);
        }

        /// <summary>
        /// This method represents the implementation of JSON.NET. JSON.NET supports .NET Standard 1.0.
        /// </summary>
        public void JsonNet(INetStandard10 platform)
        {
            platform.Linq();

            platform.Reflection();

            platform.Collections();
        }
    }
}
	using System;

	namespace Analogy
	{
	// Each interface represents a target framework and methods represents groups of APIs available on that target framework.
	// The goal is to show the relationship between .NET Standard API surface and other .NET platforms


	// .NET Standard

	interface INetStandard10
	{
	void Primitives();
	void Reflection();
	void Tasks();
	void Collections();
	void Linq();
	}

	interface INetStandard11 : INetStandard10
	{
	void ConcurrentCollections();
	void InteropServices();
	}

	interface INetStandard12 : INetStandard11
	{
	void ThreadingTimer();
	}

	interface INetStandard13 : INetStandard12
	{
	void FileSystem();
	void Console();
	void ThreadPool();
	void Process();
	void Sockets();

	void AsyncLocal();
	}

	interface INetStandard14 : INetStandard13
	{
	void IsolatedStorage();
	}

	interface INetStandard15 : INetStandard14
	{
	void AssemblyLoadContext();
	}

	// .NET Framework

	interface INetFramework45 : INetStandard11
	{
	void FileSystem();
	void Console();
	void ThreadPool();
	void Crypto();
	void WebSockets();
	void Process();
	void Sockets();

	void AppDomain();
	void Xml();
	void Drawing();
	void SystemWeb();
	void WPF();
	void WindowsForms();
	void WCF();
	}

	interface INetFramework451 : INetFramework45, INetStandard12
	{
	// TODO: .NET Framework 4.5.1 specific APIs
	}

	interface INetFramework452 : INetFramework451, INetStandard12
	{
	// TODO: .NET Framework 4.5.2 specific APIs
	}

	interface INetFramework46 : INetFramework452, INetStandard13
	{
	// TODO: .NET Framework 4.6 specific APIs
	}

	interface INetFramework461 : INetFramework46, INetStandard14
	{
	// TODO: .NET Framework 4.6.1 specific APIs
	}

	interface INetFramework462 : INetFramework461, INetStandard15
	{
	// TODO: .NET Framework 4.6 specific APIs
	}

	// Mono

	interface IMono43 : INetFramework46
	{
	void MonoSpecificApi();
	}

	// Windows Universal Platform

	interface IWindowsUniversalPlatform : INetStandard14
	{
	void GPS();
	void Xaml();
	}

	// Xamarin

	interface IXamarinIOS : INetStandard15
	{
	void AppleAPIs();
	}

	interface IXamarinAndroid : INetStandard15
	{
	void GoogleAPIs();
	}

	// .NET Core

	interface INetCoreApp10 : INetStandard15
	{

	}

	// Future platform

	interface ISomeFuturePlatform : INetStandard13
	{
	// A future platform chooses to implement a specific .NET Standard version.
	// All libraries that target that version are instantly compatible with this new
	// platform
	}
	}
	namespace Analogy
	{
	/// <summary>
	/// This example shows that a library that needs access to target .NET Standard 1.3
	/// can only access APIs available in that .NET Standard. Even though similar the APIs exist on .NET
	/// Framework 4.5, it implements a version of .NET Standard that isn't compatible with the library.
	/// </summary>INetCoreApp10
	class Example1
	{
	public void Net45Application(INetFramework45 platform)
	{
	// .NET Framework 4.5 has access to all .NET Framework APIs
	platform.FileSystem();

	platform.Console();


	// This fails because .NET Framework 4.5 does not implement .NET Standard 1.3
	// Argument 1: cannot convert from 'Analogy.INetFramework45' to 'Analogy.INetStandard13'
	NetStandardLibrary13(platform);
	}

	public void NetStandardLibrary13(INetStandard13 platform)
	{
	platform.FileSystem();

	platform.Console();
	}
	}


	/// <summary>
	/// This example shows a library targeting multiple frameworks and 2 different applications
	/// using that library. MultipleTargetsLibrary needs access to the FileSystem, that API was only available
	/// in .NET Standard 1.3. .NET Standard 1.3 only works with .NET Framework 4.6. Because of this
	/// MultipleTargetsLibrary needs to add support for .NET Framework 4.5 explicitly.
	/// </summary>
	class Example2
	{
	public void Net45Application(INetFramework451 platform)
	{
	// On the .NET 4.5.1 application, the INetFramework45 implementation is choson
	MultipleTargetsLibrary(platform);
	}

	public void NetCoreApplication(INetCoreApp10 platform)
	{
	// On the .NET Core 1.0 application, the INetStandard13 implementation is choson
	MultipleTargetsLibrary(platform);
	}

	public void MultipleTargetsLibrary(INetFramework45 platform)
	{
	platform.FileSystem();
	}

	public void MultipleTargetsLibrary(INetStandard13 platform)
	{
	platform.FileSystem();
	}
	}

	/// <summary>
	/// This example shows how future platforms can be added without the need to change libraries that
	/// target the .NET Standard. JSON.NET targets .NET Standard 1.0 and can run on ANY platform that implements
	/// the standard.
	/// </summary>
	class Example3
	{
	/// <summary>
	/// This future platform implements .NET Standard 1.3
	/// </summary>
	public void FuturePlatformApplication(ISomeFuturePlatform platform)
	{
	// You are able to use JSON.NET with the future platform without recompiling JSON.NET
	JsonNet(platform);
	}

	/// <summary>
	/// This method represents the implementation of JSON.NET. JSON.NET supports .NET Standard 1.0.
	/// </summary>
	public void JsonNet(INetStandard10 platform)
	{
	platform.Linq();

	platform.Reflection();

	platform.Collections();
	}
	}
	}