[methods aliases] Features for Function Type and load function as argument

compiler/compilation/CompilationTask.cs

@@ -222,6 +222,7 @@ private bool ProcessFiles(IReadOnlyCollection<FileInfo> files, IReadOnlyCollecti
             Target.AST.Select(x => (x.Key, x.Value))
                 .Pipe(x => Status.VeinStatus($"Linking [grey]'{x.Key.Name}'[/]..."))
                 .SelectMany(LinkClasses)
+                .Concat(aliasesQueue.SelectMany(RegenerateAliases))
                 .ToList()
                 .Pipe(LinkMetadata)
                 .Pipe(ShitcodePlug)

compiler/compilation/parts/args.cs

@@ -19,8 +19,12 @@ private VeinArgumentRef[] GenerateArgument(MethodDeclarationSyntax method, Docum
             throw new SkipStatementException();
         }
 
-        if (method.Modifiers.All(x => x.ModificatorKind != ModificatorKind.Static))
-            args.Add(new VeinArgumentRef(VeinArgumentRef.THIS_ARGUMENT, FetchType(method.OwnerClass.Identifier, doc)));
+        if (!method.IsMethodType) // check method has linked to class, otherwise it is an anonymous method type
+        {
+            if (method.Modifiers.All(x => x.ModificatorKind != ModificatorKind.Static))
+                args.Add(new VeinArgumentRef(VeinArgumentRef.THIS_ARGUMENT, FetchType(method.OwnerClass.Identifier, doc)));
+        }
+
 
         if (method.Parameters.Count == 0)
             return args.ToArray();
@@ -39,30 +43,47 @@ private IEnumerable<VeinArgumentRef> Convert(List<ParameterSyntax> args, MethodD
             var constraints =
                 method.TypeParameterConstraints.FirstOrDefault(x => x.GenericIndex.Typeword.Equals(parameter.Type));
 
-            var classGeneric = method.OwnerClass.GenericTypes.FirstOrDefault(x => x.Typeword.Equals(parameter.Type));
-            var classGenericConstrains = method.OwnerClass.TypeParameterConstraints.FirstOrDefault(x => x.GenericIndex.Typeword.Equals(parameter.Type));
-
-            if (generic is not null && classGeneric is not null)
+            if (!method.IsMethodType)
             {
-                Log.Defer.Error($"Detected conflict of declaration generic types, generic type '[red bold]{parameter.Type.Identifier}[/]' " +
-                                $"is declared in the '[red bold]{method.Identifier}[/]' method and in the '[red bold]{method.OwnerClass.Identifier}[/]' class", generic, method.OwnerDocument);
-                throw new SkipStatementException();
-            }
+                var classGeneric = method.OwnerClass!.GenericTypes?.FirstOrDefault(x => x.Typeword.Equals(parameter.Type));
+                var classGenericConstrains = method.OwnerClass!.TypeParameterConstraints?.FirstOrDefault(x => x.GenericIndex.Typeword.Equals(parameter.Type));
 
-            if (generic is not null && constraints is not null)
-                yield return new VeinArgumentRef(name,
-                    generic.Typeword.ToTypeArg([constraints.ToConstraint(selector)]));
-            else if (generic is not null)
-                yield return new VeinArgumentRef(name, generic.Typeword.ToTypeArg([]));
-            else if (classGeneric is not null && classGenericConstrains is not null)
-                yield return new VeinArgumentRef(name,
-                    classGeneric.Typeword.ToTypeArg([classGenericConstrains.ToConstraint(selector)]));
-            else if (classGeneric is not null)
-                yield return new VeinArgumentRef(name, classGeneric.Typeword.ToTypeArg([]));
-            else if(parameter.Type.IsSelf)
-                yield return new VeinArgumentRef(name, FetchType(method.OwnerClass.Identifier, method.OwnerDocument));
+                if (generic is not null && classGeneric is not null)
+                {
+                    Log.Defer.Error($"Detected conflict of declaration generic types, generic type '[red bold]{parameter.Type.Identifier}[/]' " +
+                                    $"is declared in the '[red bold]{method.Identifier}[/]' method and in the '[red bold]{method.OwnerClass!.Identifier}[/]' class", generic, method.OwnerDocument);
+                    throw new SkipStatementException();
+                }
+                if (generic is not null && constraints is not null)
+                    yield return new VeinArgumentRef(name,
+                        generic.Typeword.ToTypeArg([constraints.ToConstraint(selector)]));
+                else if (generic is not null)
+                    yield return new VeinArgumentRef(name, generic.Typeword.ToTypeArg([]));
+                else if (classGeneric is not null && classGenericConstrains is not null)
+                    yield return new VeinArgumentRef(name,
+                        classGeneric.Typeword.ToTypeArg([classGenericConstrains.ToConstraint(selector)]));
+                else if (classGeneric is not null)
+                    yield return new VeinArgumentRef(name, classGeneric.Typeword.ToTypeArg([]));
+                else if (parameter.Type.IsSelf)
+                    yield return new VeinArgumentRef(name, FetchType(method.OwnerClass.Identifier, method.OwnerDocument));
+                else
+                    yield return new VeinArgumentRef(name, FetchType(parameter.Type, method.OwnerDocument));
+            }
             else
-                yield return new VeinArgumentRef(name, FetchType(parameter.Type, method.OwnerDocument));
+            {
+                if (generic is not null && constraints is not null)
+                    yield return new VeinArgumentRef(name,
+                        generic.Typeword.ToTypeArg([constraints.ToConstraint(selector)]));
+                else if (generic is not null)
+                    yield return new VeinArgumentRef(name, generic.Typeword.ToTypeArg([]));
+                else if (parameter.Type.IsSelf)
+                {
+                    Log.Defer.Error($"self type is not supported in method type '[red bold]{parameter.Type.Identifier}[/]", parameter, method.OwnerDocument);
+                    throw new SkipStatementException();
+                }
+                else
+                    yield return new VeinArgumentRef(name, FetchType(parameter.Type, method.OwnerDocument));
+            }
         }
     }
 }

compiler/compilation/parts/classes.cs

@@ -1,23 +1,27 @@
 namespace vein.compilation;
 
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using exceptions;
+using extensions;
 using ishtar;
 using ishtar.emit;
 using MoreLinq;
 using runtime;
 using syntax;
+using vein.reflection;
+using static runtime.MethodFlags;
 
 public partial class CompilationTask
 {
     public void LinkMetadata((ClassBuilder @class, MemberDeclarationSyntax member) x)
     {
-        if (x.member is not ClassDeclarationSyntax)
+        if (x.member is not ClassDeclarationSyntax clazz)
             return;
 
-        var (@class, member) = (x.@class, x.member as ClassDeclarationSyntax);
+        var (@class, member) = (x.@class, xMember: clazz);
         var doc = member.OwnerDocument;
         @class.Flags = GenerateClassFlags(member);
 
@@ -146,6 +150,9 @@ public void GenerateLinksForAliases(DocumentDeclaration doc)
     {
 
     }
+
+    private Queue<(DocumentDeclaration doc, VeinCore types)> aliasesQueue { get; } = new();
+
     public List<(ClassBuilder clazz, MemberDeclarationSyntax member)> LinkClasses(DocumentDeclaration doc, VeinCore types)
     {
         var classes = new List<(ClassBuilder clazz, MemberDeclarationSyntax member)>();
@@ -157,6 +164,9 @@ public void GenerateLinksForAliases(DocumentDeclaration doc)
                 Status.VeinStatus($"Regeneration class [grey]'{clazz.Identifier}'[/]");
                 clazz.OwnerDocument = doc;
                 var result = CompileClass(clazz, doc, types);
+
+                Debug.WriteLine($"compiled class '{result.FullName}'");
+
                 Context.Classes.Add(result.FullName, result);
                 classes.Add((result, clazz));
             }
@@ -171,22 +181,107 @@ public void GenerateLinksForAliases(DocumentDeclaration doc)
             else
                 Log.Defer.Warn($"[grey]Member[/] [yellow underline]'{member.GetType().Name}'[/] [grey]is not supported.[/]");
         }
+
+        if (doc.Aliases.Any()) aliasesQueue.Enqueue((doc, types));
+
+        return classes;
+    }
+
+    private List<(ClassBuilder clazz, MemberDeclarationSyntax member)> RegenerateAliases(
+        (DocumentDeclaration doc, VeinCore types) data)
+        => RegenerateAliases(data.doc, data.types);
+
+    private List<(ClassBuilder clazz, MemberDeclarationSyntax member)> RegenerateAliases(DocumentDeclaration doc, VeinCore types)
+    {
+        var classes = new List<(ClassBuilder clazz, MemberDeclarationSyntax member)>();
         foreach (var alias in doc.Aliases)
         {
             if (alias.IsType)
             {
                 var type = FetchType(alias.Type!.Typeword, doc);
                 Context.Module.alias_table.Add(new VeinAliasType($"{module.Name}%global::{doc.Name}/{alias.AliasName.ExpressionString}",
-                    type));
+                type));
+
+                Status.VeinStatus($"Regeneration type alias [grey]'{type}'[/] -> [grey]'{alias.AliasName.ExpressionString}'[/]");
+
                 KnowClasses.Add(alias.AliasName, type);
             }
             else
-                Log.Defer.Warn($"Method [grey]Alias[/] [yellow underline]'{alias.AliasName.ExpressionString}'[/] [grey]is not supported.[/]");
+            {
+                var delegateClass = DefineDelegateClass(alias, doc, types);
+
+                Status.VeinStatus($"Regeneration method alias [grey]'{delegateClass.FullName}'[/]");
+
+                delegateClass.TypeCode = VeinTypeCode.TYPE_FUNCTION;
+                Context.Classes.Add(delegateClass.FullName, delegateClass);
+                classes.Add((delegateClass, null!));
+            }
         }
 
         return classes;
     }
 
+    public ClassBuilder DefineDelegateClass(AliasSyntax alias, DocumentDeclaration doc, VeinCore types)
+    {
+        var aliasName = new QualityTypeName(module.Name, alias.AliasName.ExpressionString, $"global::{doc.Name}");
+        var multicastFnType = new QualityTypeName("std", "FunctionMulticast", $"global::std");
+
+        var args = GenerateArgument(alias.MethodDeclaration!, doc);
+
+        var retType = FetchType(alias.MethodDeclaration!.ReturnType, doc);
+        var sig = new VeinMethodSignature(retType, args);
+        Context.Module.alias_table.Add(new VeinAliasMethod(aliasName, sig));
+
+        var @base = module.FindType(multicastFnType, true);
+
+        var clazz = module.DefineClass(aliasName, @base)
+            .WithIncludes(doc.Includes);
+
+
+        clazz.TypeCode = VeinTypeCode.TYPE_FUNCTION;
+
+        var objType = VeinTypeCode.TYPE_OBJECT.AsClass(types);
+        var rawType = VeinTypeCode.TYPE_RAW.AsClass(types);
+
+        var ctorMethod = clazz.DefineMethod(VeinMethod.METHOD_NAME_CONSTRUCTOR, VeinTypeCode.TYPE_VOID.AsClass(types), [
+            new("fn", rawType),
+            new("scope", objType)
+        ]);
+
+
+        var scope = clazz.DefineField("_scope", FieldFlags.Internal, objType);
+        var ptrRef = clazz.DefineField("_fn", FieldFlags.Internal, rawType);
+
+        var ctorGen = ctorMethod.GetGenerator();
+
+        ctorGen.Emit(OpCodes.LDARG_0);
+        ctorGen.Emit(OpCodes.STF, ptrRef);
+        ctorGen.Emit(OpCodes.LDARG_1);
+        ctorGen.Emit(OpCodes.STF, scope);
+        ctorGen.Emit(OpCodes.RET);
+
+        var method = clazz.DefineMethod("invoke", Internal | Special,
+            sig.ReturnType,sig.Arguments.Where(VeinMethodSignature.NotThis).ToArray());
+
+        var hasThis = sig.Arguments.All(VeinMethodSignature.NotThis);
+
+        var generator = method.GetGenerator();
+
+
+        if (hasThis)
+            generator.Emit(OpCodes.LDF, scope);
+        foreach (int i in ..method.Signature.ArgLength)
+            generator.Emit(OpCodes.LDARG_S, i); // TODO optimization for LDARG_X
+
+        generator.Emit(OpCodes.LDF, ptrRef);
+        generator.Emit(OpCodes.CALL_SP);
+        generator.Emit(OpCodes.RET);
+
+
+        KnowClasses.Add(alias.AliasName, clazz);
+        return clazz;
+    }
+
     public ClassBuilder CompileClass(ClassDeclarationSyntax member, DocumentDeclaration doc, VeinCore types)
     {
         void _defineClass(ClassBuilder clz)

compiler/compilation/parts/methods.cs

@@ -173,11 +173,10 @@ private MethodFlags GenerateMethodFlags(MethodDeclarationSyntax method)
 
         if (member.IsConstructor())
         {
-            member.Identifier = new IdentifierExpression("ctor");
-
+            member.Identifier = new IdentifierExpression(VeinMethod.METHOD_NAME_CONSTRUCTOR);
             if (args.Length == 0)
                 return (clazz.GetDefaultCtor() as MethodBuilder, member);
-            var ctor = clazz.DefineMethod("ctor", GenerateMethodFlags(member), clazz, args);
+            var ctor = clazz.DefineMethod(VeinMethod.METHOD_NAME_CONSTRUCTOR, GenerateMethodFlags(member), clazz, args);
             CompileAspectFor(member, doc, ctor);
             return (ctor, member);
         }

lib/ast/syntax/VeinSyntax.cs

@@ -141,7 +141,8 @@ from parameters in MethodParameters
             from @as in Parse.Char(':').Token().Commented(this)
             from type in TypeReference.Commented(this)
             from constraints in GenericConstraintParser.Token().Optional()
-            from methodBody in BlockShortform<ReturnStatementSyntax>().Or(Block.Or(Parse.Char(';').Return(new EmptyBlockSyntax())))
+            from methodBody in BlockShortform<ReturnStatementSyntax>().Positioned()
+                .Or(Block.Or(Parse.Char(';').Return(new EmptyBlockSyntax())))
                 .Token().Positioned().Commented(this)
             select new MethodDeclarationSyntax
             {

lib/ast/syntax/ast/MethodDeclarationSyntax.cs

@@ -20,14 +20,13 @@ public class MethodDeclarationSyntax(MemberDeclarationSyntax? heading = null) :
 
         public BlockSyntax? Body { get; set; }
 
-        public bool IsAbstract => Body == null;
+        public bool IsAbstract => Body is null or EmptyBlockSyntax;
 
         public List<TypeParameterConstraintSyntax> TypeParameterConstraints { get; set; } = new();
         public List<TypeExpression> GenericTypes { get; set; } = new();
 
 
-        public string GetQualityName()
-            => $"{Identifier}({Parameters.Select(x => $"{(x.Type.IsSelf ? OwnerClass.Identifier : x.Type.Identifier)}").Join(",")})";
+        public string GetQualityName() => IsMethodType ? $"({Parameters.Select(x => $"{(x.Type.Identifier)}").Join(",")})" : $"{Identifier}({Parameters.Select(x => $"{(x.Type.IsSelf ? OwnerClass.Identifier : x.Type.Identifier)}").Join(",")})";
 
         public override MemberDeclarationSyntax WithTypeAndName(ParameterSyntax typeAndName)
         {
@@ -44,7 +43,9 @@ public override MemberDeclarationSyntax WithName(IdentifierExpression name)
 
         public bool IsConstructor() => Identifier.ExpressionString.Equals("new");
 
-        public ClassDeclarationSyntax OwnerClass { get; set; }
+        public ClassDeclarationSyntax? OwnerClass { get; set; }
+
+        public bool IsMethodType => OwnerClass is null && IsAbstract && !Modifiers.Any();
     }
 
 

lib/ast/syntax/ast/ReturnStatementSyntax.cs

@@ -1,21 +1,19 @@
-namespace vein.syntax
-{
-    using System.Collections.Generic;
-    using Sprache;
+namespace vein.syntax;
 
-    public class ReturnStatementSyntax : StatementSyntax, IPositionAware<ReturnStatementSyntax>
-    {
-        public ReturnStatementSyntax(ExpressionSyntax e) => Expression = e;
-        public override SyntaxType Kind => SyntaxType.ReturnStatement;
+using System.Collections.Generic;
+using Sprache;
 
-        public override IEnumerable<BaseSyntax> ChildNodes => GetNodes(Expression);
+public class ReturnStatementSyntax(ExpressionSyntax e) : StatementSyntax, IPositionAware<ReturnStatementSyntax>
+{
+    public override SyntaxType Kind => SyntaxType.ReturnStatement;
 
-        public ExpressionSyntax Expression { get; set; }
+    public override IEnumerable<BaseSyntax> ChildNodes => GetNodes(Expression);
 
-        public new ReturnStatementSyntax SetPos(Position startPos, int length)
-        {
-            base.SetPos(startPos, length);
-            return this;
-        }
+    public ExpressionSyntax Expression { get; set; } = e;
+
+    public new ReturnStatementSyntax SetPos(Position startPos, int length)
+    {
+        base.SetPos(startPos, length);
+        return this;
     }
 }

metadata/db_opcodes.json

@@ -112,5 +112,7 @@
   "SEH.FINALLY": 110,
   "SEH.FILTER": 111,
   "SEH.ENTER": 112,
-  "CAST": 113
+  "CAST": 113,
+  "CALL_SP": 114,
+  "LDFN": 115
 }

metadata/opcodes.def.cs

@@ -208,6 +208,14 @@ public enum OpCodeValue : ushort
 		/// </summary>
 		CALL = 0x32,
 		/// <summary>
+		/// Call operation (load pointer from stack).
+		/// </summary>
+		CALL_SP = 0x72,
+		/// <summary>
+		/// Load function pointer into stack.
+		/// </summary>
+		LDFN = 0x73,
+		/// <summary>
 		/// Load NULL into stack.
 		/// </summary>
 		LDNULL = 0x33,