Rename Permission to Precondition

src/Discord.Net.Commands/Attributes/PreconditionAttribute.cs

@@ -5,8 +5,8 @@ using System.Threading.Tasks;
 
 namespace Discord.Commands
 {
-    public abstract class PermissionAttribute : Attribute
+    public abstract class PreconditionAttribute : Attribute
     {
-        public abstract void CheckPermissions(PermissionsContext context);
+        public abstract void CheckPermissions(PreconditionContext context);
     }
 }

src/Discord.Net.Commands/Attributes/Preconditions/RequireDMAttribute.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Discord.Commands
+{
+    public class RequireDMAttribute : PreconditionAttribute
+    {
+        public override void CheckPermissions(PreconditionContext context)
+        {
+            if (context.Message.Channel is IGuildChannel)
+                context.Handled = true;
+        }
+    }
+}

src/Discord.Net.Commands/Attributes/Preconditions/RequireGuildAttribute.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Discord.Commands
+{
+    public class RequireGuildAttribute : PreconditionAttribute
+    {
+        public override void CheckPermissions(PreconditionContext context)
+        {
+            if (!(context.Message.Channel is IGuildChannel))
+                context.Handled = true;
+        }
+    }
+}