Change over the class dependency system to attributes.

src/Attributes.cs

@@ -54,4 +54,25 @@ public class CloneWithAssignmentAttribute : Attribute
     {
 
     }
+
+    /// <summary>
+    /// Signals that this class should have its ConfigErrors/PostLoad run after a different class.
+    /// </summary>
+    /// <remarks>
+    /// Currently valid and meaningful only when applied to, and referencing, things inheriting from Dec.Dec.
+    ///
+    /// Configuration order will be (mostly) stable with a fixed set of constraints into account.
+    /// </remarks>
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
+    public class SetupDependsOnAttribute : Attribute
+    {
+        private Type type;
+
+        internal Type Type => type;
+
+        public SetupDependsOnAttribute(Type type)
+        {
+            this.type = type;
+        }
+    }
 }

src/Database.cs

@@ -45,22 +45,6 @@ public static IEnumerable<Dec> List
             }
         }
 
-        /// <summary>
-        /// All registered dec root types.
-        /// </summary>
-        /// <remarks>
-        /// Types are listed in no guaranteed or stable order.
-        ///
-        /// As of this writing, this will return only Dec types that have instances. This may change someday.
-        /// </remarks>
-        public static IEnumerable<Type> ListTypes
-        {
-            get
-            {
-                return Lookup.Keys.Where(type => type.GetDecDatabaseStatus() == UtilType.DecDatabaseStatus.Root);
-            }
-        }
-
         /// <summary>
         /// Retrieves a dec by base dec type and name.
         /// </summary>
@@ -79,23 +63,6 @@ public static Dec Get(Type type, string name)
             return typedict.TryGetValue(name);
         }
 
-        /// <summary>
-        /// Retrieves a list of decs of a given type.
-        /// </summary>
-        /// <remarks>
-        /// Returns null if no such dec exists.
-        /// </remarks>
-        public static IEnumerable<Dec> ListOfType(Type type)
-        {
-            if (!Lookup.ContainsKey(type))
-            {
-                WarnOnEmpty();
-                return Enumerable.Empty<Dec>();
-            }
-
-            return Lookup[type].Values;
-        }
-
         /// <summary>
         /// Creates a Dec.
         /// </summary>

src/Parser.cs

@@ -89,9 +89,9 @@ public void AddStream(Parser.FileType fileType, Stream stream, string identifier
         /// The `dependencies` parameter can be used to feed in dependencies for the PostLoad function.
         /// This is a placeholder and is probably going to be replaced at some point, though only with something more capable.
         /// </remarks>
-        public void Finish(List<Dag<Type>.Dependency> postLoadDependencies = null)
+        public void Finish()
         {
-            parserModdable.Finish(postLoadDependencies);
+            parserModdable.Finish();
         }
     }
 }

src/ParserModular.cs

@@ -249,7 +249,7 @@ public Module CreateModule(string name)
         /// The `dependencies` parameter can be used to feed in dependencies for the PostLoad function.
         /// This is a placeholder and is probably going to be replaced at some point, though only with something more capable.
         /// </remarks>
-        public void Finish(List<Dag<Type>.Dependency> postLoadDependencies = null)
+        public void Finish()
         {
             using (var _ = new CultureInfoScope(Config.CultureInfo))
             {
@@ -464,12 +464,49 @@ public void Finish(List<Dag<Type>.Dependency> postLoadDependencies = null)
                 }
                 s_Status = Status.Finalizing;
 
-                // figure out our config/postload order
-                var postprocessOrder = Dag<Type>.CalculateOrder(Database.ListTypes, postLoadDependencies ?? new List<Dag<Type>.Dependency>(), t => t.FullName);
+                // figure out our config/postload order; first we just run over all the Decs and collate classes
+                var decTypes = new Dictionary<Type, List<Dec>>();
+                foreach (var dec in Database.List)
+                {
+                    var list = decTypes.TryGetValue(dec.GetType());
+                    if (list == null)
+                    {
+                        list = new List<Dec>();
+                        decTypes[dec.GetType()] = list;
+                    }
+
+                    list.Add(dec);
+                }
+
+                List<Dag<Type>.Dependency> postLoadDependencies = new List<Dag<Type>.Dependency>();
+                foreach (var type in decTypes)
+                {
+                    foreach (var rsaa in type.Key.GetCustomAttributes<SetupDependsOnAttribute>())
+                    {
+                        var dependsOn = rsaa.Type;
+
+                        // make sure it inherits from Dec.Dec
+                        if (!dependsOn.IsSubclassOf(typeof(Dec)))
+                        {
+                            Dbg.Err($"{type.Key} has a SetupDependsOnAttribute on {dependsOn}, but {dependsOn} is not a Dec type");
+                            continue;
+                        }
+
+                        if (!decTypes.ContainsKey(rsaa.Type))
+                        {
+                            Dbg.Err($"{type.Key} has a SetupDependsOnAttribute on {dependsOn}, but {dependsOn} is not a known Dec type; this might result in weird behavior, either create an instance of {dependsOn} or pester ZorbaTHut on Discord if you need this fixed");
+                            continue;
+                        }
+
+                        postLoadDependencies.Add(new Dag<Type>.Dependency { before = rsaa.Type, after = type.Key });
+                    }
+                }
+
+                var postprocessOrder = Dag<Type>.CalculateOrder(decTypes.Keys, postLoadDependencies, t => t.Name);
 
                 foreach (var type in postprocessOrder)
                 {
-                    foreach (var dec in Database.ListOfType(type))
+                    foreach (var dec in decTypes[type])
                     {
                         try
                         {
@@ -484,7 +521,7 @@ public void Finish(List<Dag<Type>.Dependency> postLoadDependencies = null)
 
                 foreach (var type in postprocessOrder)
                 {
-                    foreach (var dec in Database.ListOfType(type))
+                    foreach (var dec in decTypes[type])
                     {
                         try
                         {