Add an ICoreService interface that interfaces such as IEmulator and IDebuggable inherit

BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj

@@ -61,6 +61,7 @@
     <Compile Include="Interfaces\CoreComms.cs" />
     <Compile Include="Interfaces\IController.cs" />
     <Compile Include="Interfaces\ICoreFileProvider.cs" />
+    <Compile Include="Interfaces\ICoreService.cs" />
     <Compile Include="Interfaces\IDebuggable.cs" />
     <Compile Include="Interfaces\IEmulator.cs" />
     <Compile Include="Interfaces\IMemoryDomains.cs" />

BizHawk.Emulation.Common/Interfaces/ICoreService.cs

@@ -0,0 +1,11 @@
+namespace BizHawk.Emulation.Common
+{
+	/// <summary>
+	/// This interface specifies that an interface or implementation is a emulator core service, such as IDebuggable,
+	/// but is an optional part of the core functionality
+	/// Clients should gracefully handle an IEmulator that has a missing or partial implementation of one of these services
+	/// </summary>
+	public interface ICoreService
+	{
+	}
+}

BizHawk.Emulation.Common/Interfaces/IDebuggable.cs

@@ -2,7 +2,7 @@
 
 namespace BizHawk.Emulation.Common
 {
-	public interface IDebuggable : IEmulator
+	public interface IDebuggable : IEmulator, ICoreService
 	{
 		/// <summary>
 		/// Returns a list of Cpu registers and their current state

BizHawk.Emulation.Common/Interfaces/IEmulator.cs

@@ -4,7 +4,7 @@ using System.IO;
 
 namespace BizHawk.Emulation.Common
 {
-	public interface IEmulator : IDisposable
+	public interface IEmulator : ICoreService, IDisposable
 	{
 		/// <summary>
 		/// Video provider to the client

BizHawk.Emulation.Common/Interfaces/IMemoryDomains.cs

@@ -1,6 +1,6 @@
 namespace BizHawk.Emulation.Common
 {
-	public interface IMemoryDomains : IEmulator
+	public interface IMemoryDomains : IEmulator, ICoreService
 	{
 		///The list of all avaialble memory domains
 		/// A memory domain is a byte array that respresents a distinct part of the emulated system.

BizHawk.Emulation.Common/Interfaces/ISettable.cs

@@ -87,7 +87,7 @@ namespace BizHawk.Emulation.Common
 		}
 	}
 
-	public interface ISettable<TSettings, TSync> : IEmulator
+	public interface ISettable<TSettings, TSync> : IEmulator, ICoreService
 	{
 		// in addition to these methods, it's expected that the constructor or Load() method
 		// will take a Settings and SyncSettings object to set the initial state of the core