Assign tuple optimizer (#3160)

* branch init

* add BindCollectLightSymInfo

* moved lightsyminfo to syntaxVisitors

* LIghtSymInfo fixes

* binder 0.1

* Attributes -> SymbolAttributes

* AssignTupleOptimizer -> AssignTupleDesugar

* moved algorithm classes to AssignTupleDesugarAlgorithm namespace

* fixes and refactoring

* LightSymInfo rework

* add rebuildDebug and build units

* enable VarNamesInMethodsWithSameNameAsClassGenericParamsReplacer

* remove CollectFullLightSymInfo call

* bind now return BindResult

* change BindResult path type

* path testing

* fix Current in BindCollectLightSymInfo

* fix Current in BindCollectLightSymInfo

* fix #3116

* (the rest of the fix)

* potential symomyms handling without assigns count minimization

* assign count minimization

* rename AssignTuplesDesugar

* move NewAssignTupleDesugar

* add optimization switch

* delete AssignTupleDesugar project

* remove comments

* collect symbols from var tuples

* optimize var_tuple_def_statement and assign_var_tuple

* fix

* fix Tuple Visitor

* #3091

* #3125

* revert #3125

* #3125

* #3123

* #3123

* #3127

* fix

* del doc

* await переместил

* Перегенерировал грамматику

* s.ToLines
RenameDirectory

* Исправление ToLines

* Убрал из грамматики узлы await - случайно оставались

* Sync `.ToLines` with `System.IO.StringReader` (#3154)

* 3.9.0.3494

* add const optimization

* #3152

* #3152

---------

Co-authored-by: Sun Serega <sunserega2@gmail.com>
Co-authored-by: Ivan Bondarev <ibond84@googlemail.com>
Co-authored-by: Mikhalkovich Stanislav <miks@math.sfedu.ru>
Co-authored-by: Артём Филонов <afilono@sfedu.ru>

Compiler/Compiler.cs

@@ -2709,9 +2709,12 @@ namespace PascalABCCompiler
 
             if (!PCUFileNamesDictionary.TryGetValue(cacheKey, out var fileNameWithPriority))
             {
-                if (FindFileWithExtensionInDirs(fileName, out _, currentPath) is string resultFileName1)
+                if (Path.GetExtension(fileName) != CompilerOptions.CompiledUnitExtension)
+                    fileNameWithPriority = null;
+
+                else if (FindFileWithExtensionInDirs(fileName, out _, currentPath) is string resultFileName1)
                     fileNameWithPriority = Tuple.Create(resultFileName1, 1);
-                else if (FindFileWithExtensionInDirs(Path.GetFileName(fileName), out _, CompilerOptions.OutputDirectory) is string resultFileName2)
+                else if (CompilerOptions.OutputDirectory != CompilerOptions.SourceFileDirectory && FindFileWithExtensionInDirs(Path.GetFileName(fileName), out _, CompilerOptions.OutputDirectory) is string resultFileName2)
                     fileNameWithPriority = Tuple.Create(resultFileName2, 2);
                 else if (FindFileWithExtensionInDirs(fileName, out var dirIndex, CompilerOptions.SearchDirectories.ToArray()) is string resultFileName3)
                     fileNameWithPriority = Tuple.Create(resultFileName3, 3 + dirIndex);
@@ -2731,6 +2734,7 @@ namespace PascalABCCompiler
 
             if (!SourceFileNamesDictionary.TryGetValue(cacheKey, out var fileNameWithPriority))
 			{
+
 				if (FindSourceFileNameInDirs(fileName, out _, currentPath) is string resultFileName1)
                     fileNameWithPriority = Tuple.Create(resultFileName1, 1);
                 else if (FindSourceFileNameInDirs(fileName, out var dirIndex, CompilerOptions.SearchDirectories.ToArray()) is string resultFileName2)
@@ -3362,7 +3366,17 @@ namespace PascalABCCompiler
             // It's not always possible to solve by re-ordering the references, since there are cases of
             // mutually-dependent assemblies (i.e. dependency loops) in the wild.
             foreach (var reference in referenceDirectives)
+            {
+                try
+                {
                     PreloadReference(reference);
+                }
+                catch (FileLoadException ex)
+                {
+                    throw new CommonCompilerError(ex.Message, compilationUnit.SyntaxTree.file_name, reference.location.begin_line_num, reference.location.end_line_num);
+                }
+            }
+                
                 
             foreach (var reference in referenceDirectives)
                 CompileReference(dlls, reference);

Compiler/PCU/PCUReader.cs

@@ -1847,7 +1847,10 @@ namespace PascalABCCompiler.PCU
             common_method_node raise_meth = null;
             if (CanReadObject())
             raise_meth = GetClassMethod(br.ReadInt32());
-            class_field cf = GetClassField(br.ReadInt32());
+            int field_off = br.ReadInt32();
+            class_field cf = null;
+            if (field_off > 0)
+                cf = GetClassField(field_off);
             common_type_node cont = (common_type_node)GetTypeReference(br.ReadInt32());
             if (name==null)
                 name = GetStringInClass(cont, name_ref);

Compiler/PCU/PCUWriter.cs

@@ -3021,7 +3021,10 @@ namespace PascalABCCompiler.PCU
 			bw.Write(GetMemberOffset(_event.remove_method));
 			if (CanWriteObject(_event.raise_method))
 			bw.Write(GetMemberOffset(_event.raise_method));
+            if (!_event.cont_type.IsInterface)
                 bw.Write(GetMemberOffset(_event.field));
+            else
+                bw.Write(0);
 			bw.Write(offset);
 			bw.Write((byte)_event.field_access_level);
 			bw.Write((byte)_event.polymorphic_state);

Configuration/GlobalAssemblyInfo.cs

@@ -15,7 +15,7 @@ internal static class RevisionClass
 	public const string Major = "3";
 	public const string Minor = "9";
 	public const string Build = "0";
-	public const string Revision = "3488";
+	public const string Revision = "3494";
 
         public const string MainVersion = Major + "." + Minor;
 	public const string FullVersion = Major + "." + Minor + "." + Build + "." + Revision;

Configuration/Version.defs

@@ -1,4 +1,4 @@
 %COREVERSION%=0
-%REVISION%=3488
+%REVISION%=3494
 %MINOR%=9
 %MAJOR%=3

Languages/Pascal/PascalABCParserNewSaushkin/ABCPascal.cs

@@ -1,9 +1,9 @@
 //
 //  This CSharp output file generated by Gardens Point LEX
 //  Version:  1.1.3.301
-//  Machine:  DESKTOP-V3E9T2U
+//  Machine:  DESKTOP-G8V08V4
-//  DateTime: 25.05.2024 22:13:44
+//  DateTime: 17.06.2024 16:43:45
-//  UserName: alex
+//  UserName: ?????????
 //  GPLEX input file <ABCPascal.lex>
 //  GPLEX frame file <embedded resource>
 //

Languages/Pascal/PascalABCParserNewSaushkin/ABCPascal.y

@@ -3373,8 +3373,6 @@ expr_l1_for_lambda
 expr_dq
 	: relop_expr
 		{ $$ = $1; }
-	| tkAwait relop_expr
-		{ $$ = $2; }
 	| expr_dq tkDoubleQuestion relop_expr
 		{ $$ = new double_question_node($1 as expression, $3 as expression, @$);}
 	;

Languages/Pascal/PascalABCParserNewSaushkin/PABC.ymc

@@ -377,6 +377,9 @@ script=
 
 
 
+
+
+
 
 
 

Languages/Pascal/SyntaxTreeConverters/SyntaxTreeConverters/StandardSyntaxConverter.cs

@@ -15,7 +15,9 @@ namespace Languages.Pascal.Frontend.Converters
         
         protected override syntax_tree_node ApplyConcreteConversions(syntax_tree_node root)
         {
+            root.FillParentsInAllChilds();
 
+            var binder = new BindCollectLightSymInfo(root as compilation_unit);
 #if DEBUG
             //            var stat = new ABCStatisticsVisitor();
             //            stat.ProcessNode(root);
@@ -42,9 +44,9 @@ namespace Languages.Pascal.Frontend.Converters
 #if DEBUG
             //new SimplePrettyPrinterVisitor("D:/out.txt").ProcessNode(root);
 #endif
-
+            bool optimize_tuple_assign = true;
             // tuple_node
-            TupleVisitor.New.ProcessNode(root);
+            TupleVisitor.Create(optimize_tuple_assign).ProcessNode(root);
 
             // index 
             IndexVisitor.New.ProcessNode(root);
@@ -55,8 +57,10 @@ namespace Languages.Pascal.Frontend.Converters
 
             // теперь коллизия с (a[1:6], a[6:11]):= (a[6:11], a[1:6]);
             // assign_tuple и assign_var_tuple
+            if (!optimize_tuple_assign)
                 AssignTuplesDesugarVisitor.New.ProcessNode(root); // теперь это - на семантике
-            
+            else 
+                NewAssignTuplesDesugarVisitor.Create(binder).ProcessNode(root);
 
             // question_point_desugar_visitor
             QuestionPointDesugarVisitor.New.ProcessNode(root);

NETGenerator/NETGenerator.cs

@@ -4707,9 +4707,12 @@ namespace PascalABCCompiler.NETGenerator
         {
             ICommonTypeNode ctn = init_value.type as ICommonTypeNode;
             IExpressionNode[] FieldValues = init_value.FieldValues;
-            ICommonClassFieldNode[] Fields = ctn.fields;
+            List<ICommonClassFieldNode> Fields = new List<ICommonClassFieldNode>();
+            foreach (var field in ctn.fields)
+                if (field.polymorphic_state != polymorphic_state.ps_static)
+                    Fields.Add(field);
 
-            for (int i = 0; i < Fields.Length; i++)
+            for (int i = 0; i < Fields.Count; i++)
             {
                 FldInfo field = helper.GetField(Fields[i]);
                 if (FieldValues[i] is IArrayInitializer)
@@ -4750,9 +4753,12 @@ namespace PascalABCCompiler.NETGenerator
         {
             ICommonTypeNode ctn = init_value.type as ICommonTypeNode;
             IConstantNode[] FieldValues = init_value.FieldValues;
-            ICommonClassFieldNode[] Fields = ctn.fields;
+            List<ICommonClassFieldNode> Fields = new List<ICommonClassFieldNode>();
+            foreach (var field in ctn.fields)
+                if (field.polymorphic_state != polymorphic_state.ps_static)
+                    Fields.Add(field);
 
-            for (int i = 0; i < Fields.Length; i++)
+            for (int i = 0; i < Fields.Count; i++)
             {
                 FldInfo field = helper.GetField(Fields[i]);
                 if (FieldValues[i] is IArrayConstantNode)

PascalABCNET.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 17
+# Visual Studio Version 16
-VisualStudioVersion = 17.8.34309.116
+VisualStudioVersion = 16.0.34301.259
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "VisualPascalABCNET", "VisualPascalABCNET", "{26843C5D-9D7E-4C2C-AC14-2D227FA5592E}"
 EndProject

Release/pabcversion.txt

@@ -1 +1 @@
-3.9.0.3488
+3.9.0.3494

ReleaseGenerators/PascalABCNET_version.nsh

@@ -1 +1 @@
-!define VERSION '3.9.0.3488'
+!define VERSION '3.9.0.3494'

SyntaxVisitors/LightSymInfoVisitors/BindCollectLightSymInfo.cs

@@ -1,4 +1,5 @@
-
+using System.Collections.Generic;
+using System.Linq;
 
 namespace PascalABCCompiler.SyntaxTree
 {
@@ -12,22 +13,23 @@ namespace PascalABCCompiler.SyntaxTree
         {
             Current = Root;
             visit(root);
+            Current = null;
         }
 
-        public SymInfoSyntax bind(ident node)
+        public BindResult bind(ident node)
         {
-            ///Console.WriteLine("searching " + node.ToString());
+         
+            Current = null;
             syntax_tree_node cur_node = node;
+            var path = new Queue<ScopeSyntax>();
             while (cur_node != null)
             {
-               // Console.WriteLine("cur_node: " + cur_node.ToString());
 
                 if (AbstractScopeCreator.IsScopeCreator(cur_node))
                 {
 
-                    //Console.WriteLine("checking scope" + cur_node.ToString())
                     var cur_scope = scopeCreator.GetScope(cur_node);
-                    //Console.WriteLine(cur_scope.ToString() + ": " + cur_scope.Symbols.Count);
+                    path.Enqueue(cur_scope);
                     var prev_scope = Current;
                     
                     if (prev_scope != null)
@@ -36,11 +38,10 @@ namespace PascalABCCompiler.SyntaxTree
                     Current = cur_scope;
                     if (cur_scope.Parent == null && !(Current is GlobalScopeSyntax))
                     {
-                        //Console.WriteLine("visiting " + cur_node.ToString());
                         cur_node.visit(this);
                     }
                     var res = Current.bind(node);
-                    if (res != null) return res;
+                    if (res != null) return new BindResult(res, path.ToList());
                 }
                 cur_node = cur_node.Parent;
             }

SyntaxVisitors/LightSymInfoVisitors/CollectLightSymInfoVisitor.cs

@@ -38,6 +38,20 @@ namespace PascalABCCompiler.SyntaxTree
             AddSymbols(vd.vars.list, SymKind.var, vd.vars_type, attr);
             base.visit(vd);
         }
+
+        public override void visit(assign_var_tuple node)
+        {
+            AddSymbols(node.idents.idents, SymKind.var);
+            base.visit(node);
+        }
+
+        public override void visit(var_tuple_def_statement node)
+        {
+            var attr = node.var_attr == definition_attribute.Static ? SymbolAttributes.class_attr : 0;
+            AddSymbols(node.vars.list, SymKind.var, node.vars_type, attr);
+            base.visit(node);
+        }
+
         public override void visit(formal_parameters fp)
         {
             foreach (var pg in fp.params_list)

SyntaxVisitors/LightSymInfoVisitors/LightScopeHelperClasses.cs

@@ -53,6 +53,19 @@ namespace PascalABCCompiler.SyntaxTree
         }
     }
 
+    public class BindResult {
+
+        public SymInfoSyntax symInfo;
+        public List<ScopeSyntax> path;
+
+        public BindResult(SymInfoSyntax s, List<ScopeSyntax> p)
+        {
+            symInfo = s;
+            path = p;
+        }
+
+    }
+
     public abstract class ScopeSyntax
     {
         public syntax_tree_node node;

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/NewAssignTuplesDesugarVisitor.cs

@@ -0,0 +1,102 @@
+using System.Collections.Generic;
+using System.Linq;
+using AssignTupleDesugarAlgorithm;
+using PascalABCCompiler.SyntaxTree;
+
+namespace SyntaxVisitors.SugarVisitors
+{
+    public class NewAssignTuplesDesugarVisitor : AssignTuplesDesugarVisitor
+    {
+
+        private BindCollectLightSymInfo binder;
+
+    
+        public static NewAssignTuplesDesugarVisitor Create(BindCollectLightSymInfo binder)
+        {
+            return new NewAssignTuplesDesugarVisitor(binder);
+        }
+
+        public NewAssignTuplesDesugarVisitor(BindCollectLightSymInfo binder)
+        {
+            this.binder = binder; 
+        }
+     
+
+        List<statement> desugar(tuple_node tn, addressed_value_list vars)
+        {
+            var order = Assign.getAssignOrder(tn, vars, binder);
+            var assigns = new List<statement>();
+            foreach (var a in order)
+            {
+                if (a.to is TempSymbol ts)
+                {
+                    var cur = new var_def_statement(ts.node as ident, a.from.node, tn.Parent.source_context);
+                    assigns.Add(new var_statement(cur, tn.Parent.source_context));
+                }
+                else
+                {
+                    var cur = new assign(a.to.node as addressed_value, a.from.node, tn.Parent.source_context);
+                    assigns.Add(cur);
+                }
+            }
+            return assigns;
+        }
+
+
+        public override void visit(assign_tuple node)
+        {
+            if (node.expr is tuple_node tn)
+            {
+                var n = node.vars.variables.Count();
+                if (n > tn.el.Count)
+                    throw new SyntaxVisitorError("TOO_MANY_ELEMENTS_ON_LEFT_SIDE_OF_TUPLE_ASSIGNMENT", node.vars.variables[0]);
+
+                var assigns = desugar(tn, node.vars);
+                ReplaceStatementUsingParent(node, assigns);
+            }
+            else
+                base.visit(node);
+        }
+        
+        public override void visit(assign_var_tuple node)
+        {
+            if (node.expr is tuple_node tn)
+            {
+                var n = node.idents.idents.Count();
+                if (n > tn.el.Count)
+                    throw new SyntaxVisitorError("TOO_MANY_ELEMENTS_ON_LEFT_SIDE_OF_TUPLE_ASSIGNMENT", node.idents.idents[0]);
+
+                var assigns = new List<statement>();
+                for(var i =0; i < n; i++)
+                {
+                    var cur = new var_def_statement(node.idents.idents[i], tn.el.expressions[i], tn.Parent.source_context);
+                    assigns.Add(new var_statement(cur, node.source_context));
+                }
+                ReplaceStatementUsingParent(node, assigns);
+            }
+            else
+                base.visit(node);
+            
+        }
+
+        public override void visit(var_tuple_def_statement node)
+        {
+            if (node.inital_value is tuple_node tn)
+            {
+                var n = node.vars.idents.Count();
+                if (n > tn.el.Count)
+                    throw new SyntaxVisitorError("TOO_MANY_ELEMENTS_ON_LEFT_SIDE_OF_TUPLE_ASSIGNMENT", node.vars.idents[0]);
+                var assigns = new List<var_def_statement>();
+                for (var i = 0; i < n; i++)
+                {
+                    var cur = new var_def_statement(node.vars.idents[i], tn.el.expressions[i], tn.Parent.source_context);
+                    assigns.Add(cur);
+                }
+                ReplaceVarTupleDefStatementUsingParent(node, assigns);
+            }
+            else
+                base.visit(node);
+
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/Assign.cs

@@ -0,0 +1,45 @@
+using System.Collections.Generic;
+using System.Linq;
+using PascalABCCompiler.SyntaxTree;
+
+namespace AssignTupleDesugarAlgorithm
+{
+    public class Assign
+    {
+        public Symbol from;
+        public Symbol to;
+        public Assign(Symbol to, Symbol from)
+        {
+            this.to = to;
+            this.from = from;
+        }
+
+        public static List<Assign> getAssignOrder(tuple_node tn, addressed_value_list vars, BindCollectLightSymInfo binder)
+        {
+            var left = new List<Symbol>();
+            var right = new List<Symbol>();
+
+            foreach (var ex in vars.variables)
+            {
+                var s = new Symbol(ex, binder);
+                left.Add(s);
+            }
+
+
+            foreach (var ex in tn.el.expressions)
+            {
+                var s = new Symbol(ex, binder);
+                right.Add(s);
+            }
+
+      
+            var graph = GraphUtils.createAssignGraph(left, right);
+            //graph.drawGraph();
+            var order = graph.GetAssignOrder();
+            return order.Select(elem => new Assign(to: elem.to.symbol, from: elem.from.symbol)).ToList();
+        }
+
+        
+
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/AssignGraph.cs

@@ -0,0 +1,166 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace AssignTupleDesugarAlgorithm
+{
+    internal class AssignGraph : IEnumerable<SymbolNode>
+    {
+        public readonly HashSet<SymbolNode> vertexes = new HashSet<SymbolNode>();
+
+        public readonly List<Edge> edges = new List<Edge>();
+        private bool AdjStructuresNeedSync = false;
+
+        public List<Edge> assignOrder = new List<Edge>();
+        public List<Edge> assignLast = new List<Edge>();
+        public List<Edge> assignFirst = new List<Edge>();
+
+        private Dictionary<SymbolNode, List<SymbolNode>> outAdjStructure = null;
+
+        public Dictionary<SymbolNode, List<SymbolNode>> OutAdjStructure
+        {
+            get
+            {
+                if (outAdjStructure == null || AdjStructuresNeedSync)
+                {
+                    outAdjStructure = createOutAdjStructure();
+                    inAdjStructure = createInAdjStructure();
+                    AdjStructuresNeedSync = false;
+                }
+
+                return outAdjStructure;
+            }
+        }
+
+        private Dictionary<SymbolNode, List<SymbolNode>> createOutAdjStructure()
+        {
+            Dictionary<SymbolNode, List<SymbolNode>> res = new Dictionary<SymbolNode, List<SymbolNode>>();
+
+            foreach (var vert in vertexes) res.Add(vert, new List<SymbolNode>());
+
+            foreach (Edge edge in edges) res[edge.from].Add(edge.to);
+
+            return res;
+        }
+
+        private Dictionary<SymbolNode, List<SymbolNode>> inAdjStructure = null;
+
+        public Dictionary<SymbolNode, List<SymbolNode>> InAdjStructure
+        {
+            get
+            {
+                if (inAdjStructure == null || AdjStructuresNeedSync)
+                {
+                    outAdjStructure = createOutAdjStructure();
+                    inAdjStructure = createInAdjStructure();
+                    AdjStructuresNeedSync = false;
+                }
+
+                return inAdjStructure;
+            }
+        }
+
+        private Dictionary<SymbolNode, List<SymbolNode>> createInAdjStructure()
+        {
+            Dictionary<SymbolNode, List<SymbolNode>> res = new Dictionary<SymbolNode, List<SymbolNode>>();
+
+            foreach (var vert in vertexes) res.Add(vert, new List<SymbolNode>());
+
+            foreach (Edge edge in edges) res[edge.to].Add(edge.from);
+
+            return res;
+        }
+
+
+        public List<Edge> GetInEdgesForVertex(SymbolNode v) => edges.FindAll(edge => edge.to == v);
+        public List<Edge> GetOutEdgesForVertex(SymbolNode v) => edges.FindAll(edge => edge.from == v);
+
+        public void resetVertexesColor()
+        {
+            foreach (SymbolNode v in vertexes) v.resetColor();
+        }
+
+        public bool EnsureThatEveryVertexHasOneOrZeroInEdge() =>
+            vertexes.All(vert => GetInEdgesForVertex(vert).Count <= 1);
+
+        internal List<Edge> GetAssignOrder()
+        {
+            List<Edge> assignOrder = new List<Edge>();
+            assignOrder.AddRange(assignFirst);
+
+            if (vertexes.Count == 0)
+            {
+                assignOrder.AddRange(assignLast);
+                this.assignOrder = assignOrder;
+                return this.assignOrder;
+            }
+
+            var s = vertexes.First();
+
+            if (!EnsureThatEveryVertexHasOneOrZeroInEdge()) throw new Exception("Invalid assign graph!");
+
+            var cycles = this.findAllUniqueElementaryCycles();
+
+            foreach (var cycle in cycles)
+            {
+                SymbolNode cut_place = cycle[0];
+                Edge edge_to_cut = GetInEdgesForVertex(cut_place).First();
+
+                SymbolNode temp_assign_from = edge_to_cut.from;
+                SymbolNode temp_vertex = new TempSymbolNode(new TempSymbol());
+
+                assignOrder.Add(new Edge(temp_assign_from, temp_vertex));
+                assignLast.Add(new Edge(temp_vertex, cut_place));
+
+                edges.Remove(edge_to_cut);
+                AdjStructuresNeedSync = true;
+            }
+
+            List<SymbolNode> roots = vertexes.ToList().FindAll(vertex => GetInEdgesForVertex(vertex).Count == 0);
+
+            void treeTraversal(SymbolNode root)
+            {
+                foreach (SymbolNode node in OutAdjStructure[root]) treeTraversal(node);
+
+                var inEdges = GetInEdgesForVertex(root);
+                if (inEdges.Count() > 0) assignOrder.Add(inEdges.First());
+            }
+
+            foreach (SymbolNode root in roots) treeTraversal(root);
+
+            assignOrder.AddRange(assignLast);
+            this.assignOrder = assignOrder;
+            return this.assignOrder;
+        }
+
+        public AssignGraph(List<Edge> edges, List<SymbolNode> vertexes) : this(edges)
+        {
+            foreach (SymbolNode vert in vertexes) this.vertexes.Add(vert);
+        }
+
+        public AssignGraph()
+        {
+
+        }
+
+        public AssignGraph(List<Edge> e)
+        {
+            edges = e;
+            foreach (var edge in edges)
+            {
+                vertexes.Add(edge.from);
+                vertexes.Add(edge.to);
+            }
+        }
+        public IEnumerator<SymbolNode> GetEnumerator()
+        {
+            return ((IEnumerable<SymbolNode>)vertexes).GetEnumerator();
+        }
+
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            return ((IEnumerable)vertexes).GetEnumerator();
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/Cycle.cs

@@ -0,0 +1,31 @@
+using System.Collections.Generic;
+
+namespace AssignTupleDesugarAlgorithm
+{
+    internal class Cycle
+    {
+        List<SymbolNode> cycle;
+
+
+        public int Len => cycle.Count;
+
+        public Cycle(List<SymbolNode> c)
+        {
+            cycle = c;
+        }
+
+        public SymbolNode this[int i] => cycle[i % Len];
+
+
+        public override string ToString()
+        {
+            string res = "";
+            foreach (var v in cycle)
+            {
+                res += v + "->";
+            }
+
+            return res + cycle[0];
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/Edge.cs

@@ -0,0 +1,30 @@
+using System;
+
+namespace AssignTupleDesugarAlgorithm
+{
+    internal class Edge : IEquatable<Edge>, IComparable<Edge>
+    {
+        public SymbolNode from;
+        public SymbolNode to;
+        public int weight;
+
+        public Edge(SymbolNode f, SymbolNode t, int w = 0)
+        {
+            if (weight < 0) throw new ArgumentException("weight can't be negative!");
+            from = f;
+            to = t;
+            weight = w;
+        }
+
+        public int CompareTo(Edge other)
+        {
+            return weight - other.weight;
+        }
+
+        public bool Equals(Edge other)
+        {
+            if (other is null) return false;
+            return from == other.from && to == other.to;
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/GraphUtils.cs

@@ -0,0 +1,525 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+
+
+namespace AssignTupleDesugarAlgorithm
+{
+    internal static class GraphUtils
+    {
+        static private void dfs(this AssignGraph graph,
+            Action<AssignGraph> OnEnterGraph,
+            Func<AssignGraph, SymbolNode, bool> OnProcessVertex,
+            Action<AssignGraph, SymbolNode> OnEnterNode,
+            Func<AssignGraph, SymbolNode, SymbolNode, bool> OnProcessNodeChild,
+            Action<AssignGraph, SymbolNode> OnLeaveNode,
+            Action<AssignGraph> OnLeaveGraph,
+            Func<AssignGraph, SymbolNode, IEnumerable<SymbolNode>> vertexTraversalOrderFunc = null,
+            IEnumerable<SymbolNode> graphTraversalOrder = null)
+        {
+            void dfs(SymbolNode start_node,
+                Action<AssignGraph, SymbolNode> OnEnter,
+                Func<AssignGraph, SymbolNode, SymbolNode, bool> OnProcessChild,
+                Action<AssignGraph, SymbolNode> OnLeave
+            )
+            {
+                OnEnter(graph, start_node);
+                IEnumerable<SymbolNode> vertexTraversalOrder;
+                if (vertexTraversalOrderFunc == null) vertexTraversalOrder = graph.OutAdjStructure[start_node];
+                else vertexTraversalOrder = vertexTraversalOrderFunc(graph, start_node);
+                foreach (SymbolNode current_node in vertexTraversalOrder)
+                {
+                    if (OnProcessChild(graph, start_node, current_node))
+                        dfs(current_node, OnEnter, OnProcessChild, OnLeave);
+                }
+
+                OnLeave(graph, start_node);
+            }
+
+
+            if (graphTraversalOrder == null) graphTraversalOrder = graph.vertexes;
+
+            OnEnterGraph(graph);
+            foreach (SymbolNode v in graphTraversalOrder)
+            {
+                if (OnProcessVertex(graph, v))
+                    dfs(v, OnEnter: OnEnterNode, OnProcessChild: OnProcessNodeChild, OnLeave: OnLeaveNode);
+            }
+
+            OnLeaveGraph(graph);
+        }
+
+
+        private class SynonymsGraph {
+
+            public enum  Type { SAME_NAME, INDEXER}
+
+            public HashSet<int> left = new HashSet<int>();
+            public HashSet<int> right = new HashSet<int>();
+
+            public Type type;
+
+            public SynonymsGraph(Type type)
+            {
+                this.type = type;
+            }
+
+            public override string ToString()
+            {
+                var res = "";
+                if (type == Type.INDEXER)
+                    res += "Indexer";
+                else
+                    res += "Same_Name";
+                res += "graph(left[";
+                foreach (var i in left) res += i.ToString() + ",";
+                res += "], right[";
+                foreach(var i in right) res += i.ToString() + ",";
+                res += "])";
+                return res;
+            }
+
+        }
+
+        public static AssignGraph createAssignGraph(List<Symbol> left, List<Symbol> right)
+        {
+            if (right.Count < left.Count) throw new Exception("AAAA");
+
+         
+            List<SymbolNode> v_left = new List<SymbolNode>();
+            List<SymbolNode> v_right = new List<SymbolNode>();
+            List<Symbol> left_visited = new List<Symbol>();
+            List<Edge> assign_first = new List<Edge>();
+            List<Edge> assign_last = new List<Edge>();
+
+            var moved_first = new List<Edge>();
+            var moved_last = new LinkedList<Edge>();
+            var movedAssigns = new HashSet<int>();
+
+
+            void moveAssign(int i, bool toFirst)
+            {
+                Edge assign = new Edge(new SymbolNode(right[i]), new SymbolNode(left[i]));
+                if (toFirst)
+                    moved_first.Add(assign);
+                else
+                    moved_last.AddFirst(assign);
+                movedAssigns.Add(i);
+            }
+
+            void addTemp(int i, bool toFirst)
+            {
+                if(toFirst)
+                {
+                    var temp_symbol = new TempSymbol();
+                    assign_first.Add(new Edge(new SymbolNode(right[i]), new TempSymbolNode(temp_symbol)));
+                    right[i] = temp_symbol;
+                }
+                else
+                {
+                    var temp_s = new TempSymbol();
+                    assign_last.Add(new Edge(new TempSymbolNode(temp_s), new SymbolNode(left[i])));
+                    left[i] = temp_s;
+                }
+            }
+
+            // if repeated assigns or pointers -> 2n 
+            for (int i = 0; i < left.Count(); i++)
+            {
+                if (left_visited.Find(it => it.StructurallyEquals(left[i])) != null
+                    || right[i].type == Symbol.Type.POINTER
+                    || left[i].type == Symbol.Type.POINTER)
+                {
+                    var res = new AssignGraph();
+                    res.assignFirst = make2n(left, right);
+                    return res;
+                }
+                else
+                    left_visited.Add(left[i]);
+            }
+
+            //handle expressions and var params
+            for (int i = 0; i < left.Count(); i++)
+            {
+                if (right[i].type == Symbol.Type.EXPR || right[i].type == Symbol.Type.VAR_PARAM)
+                {
+                    
+                    addTemp(i, true);
+                }
+                if (left[i].type == Symbol.Type.VAR_PARAM)
+                {
+                    addTemp(i, false);
+                }
+            }
+
+            for (int i = left.Count - 1; i > -1; i--)
+            {
+                //handle loops
+                if (left[i].StructurallyEquals(right[i]))
+                {
+                    var f = new SymbolNode(right[i]);
+                    var t = new SymbolNode(left[i]);
+                    assign_first.Add(new Edge(f, t));
+                    left.RemoveAt(i);
+                    right.RemoveAt(i);
+                }
+            }
+
+
+            var indexerGraph = new SynonymsGraph(SynonymsGraph.Type.INDEXER);
+            var nameToGraph = new Dictionary<string, SynonymsGraph>();
+
+
+            for (int i = 0; i < left.Count; i++)
+            {
+                if (left[i].type == Symbol.Type.INDEXER)
+                    indexerGraph.left.Add(i);
+                else if (left[i].type == Symbol.Type.FROM_OUTER_SCOPE || left[i].type == Symbol.Type.DOT_NODE)
+                {
+                    var name = left[i].last_name;
+                    if (!nameToGraph.ContainsKey(name))
+                        nameToGraph.Add(name, new SynonymsGraph(SynonymsGraph.Type.SAME_NAME));
+                    nameToGraph[name].left.Add(i);
+                }
+                if (right[i].type == Symbol.Type.INDEXER)
+                    indexerGraph.right.Add(i);
+                else if (right[i].type == Symbol.Type.FROM_OUTER_SCOPE || right[i].type == Symbol.Type.DOT_NODE)
+                {
+                    var name = right[i].last_name;
+                    if (!nameToGraph.ContainsKey(name))
+                        nameToGraph.Add(name, new SynonymsGraph(SynonymsGraph.Type.SAME_NAME));
+                    nameToGraph[name].right.Add(i);
+                }
+            }
+
+
+            var leftSet = new HashSet<Symbol>(left);
+            var rightSet = new HashSet<Symbol>(right);
+            var graphs = new List<SynonymsGraph>();
+            graphs.AddRange(nameToGraph.Values);
+            graphs.Add(indexerGraph);
+
+            //Handle const
+            for (int i = 0; i < left.Count; i++)
+            {
+                if (right[i].type == Symbol.Type.CONST_EXPR)
+                {
+                    moveAssign(i, false);
+                }
+            }
+            void resolveGraph(SynonymsGraph sGraph)
+            {
+          
+                foreach (var i in sGraph.left)
+                {
+                    var type = right[i].type;
+                    if (type == Symbol.Type.LOCAL)
+                    {
+                        if (!leftSet.Contains(right[i]))
+                            moveAssign(i, false);
+                    }
+                    else if (type == Symbol.Type.FROM_OUTER_SCOPE)
+                    {
+                        if (!(leftSet.Contains(right[i]) || nameToGraph[right[i].last_name].left.Count() != 0))
+                            moveAssign(i, false);
+                    }
+                    else if (type == Symbol.Type.DOT_NODE)
+                    {
+                        if (nameToGraph[right[i].last_name].left.Count() == 0)
+                            moveAssign(i, false);
+                    }
+                    else if (type == Symbol.Type.INDEXER)
+                    {
+                        if (indexerGraph.left.Count() == 0)
+                            moveAssign(i, false);
+                    }
+                }
+
+                foreach (var i in sGraph.right)
+                {
+                    var type = left[i].type;
+                    if (type == Symbol.Type.LOCAL)
+                    {
+                        if (!right.Contains(left[i]))
+                           moveAssign(i, true);
+                    }
+                    else if (type == Symbol.Type.FROM_OUTER_SCOPE)
+                    {
+                        if (!(rightSet.Contains(left[i]) || nameToGraph[left[i].last_name].right.Count() != 0))
+                            moveAssign(i, true);
+                    }
+                    else if (type == Symbol.Type.DOT_NODE)
+                    {
+                        if (nameToGraph[left[i].last_name].right.Count() == 0)
+                            moveAssign(i, true);
+                    }
+                    else if (type == Symbol.Type.INDEXER)
+                    {
+                        if (indexerGraph.right.Count() == 0)
+                            moveAssign(i, true);
+                    }
+                }
+                foreach(int i in movedAssigns)
+                {
+                    sGraph.left.Remove(i);
+                    sGraph.right.Remove(i);
+                }
+
+                var l_size = sGraph.left.Count;
+                var r_size = sGraph.right.Count;
+                if (r_size == 0 || l_size == 0)
+                    return;
+
+                Edge movedFromThisGraph = null;
+                if (l_size < r_size)
+                {
+                    foreach (var i in sGraph.left)
+                    {
+                        if (sGraph.right.Contains(i))
+                        {
+                            if (movedFromThisGraph == null)
+                            {
+                                movedFromThisGraph = new Edge(new SymbolNode(right[i]), new SymbolNode(left[i]));
+                                movedAssigns.Add(i);
+                            }
+                            else
+                                addTemp(i, false);
+
+                        }
+                        else
+                            addTemp(i, false);
+                    }
+                    if (movedFromThisGraph != null)
+                        moved_last.AddFirst(movedFromThisGraph);
+                    sGraph.left.Clear();
+                }
+                else
+                {
+                    foreach (var i in sGraph.right)
+                    {
+                        if (sGraph.left.Contains(i))
+                        {
+
+                            if (movedFromThisGraph == null)
+                            {
+                                movedFromThisGraph = new Edge(new SymbolNode(right[i]), new SymbolNode(left[i]));
+                                movedAssigns.Add(i);
+                            }
+                            else
+                                addTemp(i, true);
+                        }
+                        else
+                            addTemp(i, true);
+                        
+                    }
+                    if (movedFromThisGraph != null)
+                        moved_first.Add(movedFromThisGraph);
+                    sGraph.right.Clear();
+                }
+            }
+            
+
+
+            foreach (var g in graphs)
+                resolveGraph(g);
+
+            for (int i = left.Count - 1; i >= 0; i--)
+            {
+                if (movedAssigns.Contains(i))
+                {
+                    left.RemoveAt(i);
+                    right.RemoveAt(i);
+                    movedAssigns.Remove(i);
+                }
+            }
+        
+            
+            var symbols = new Dictionary<string, SymbolNode>(); 
+
+            foreach (Symbol sym in left)
+            {
+                if (!symbols.ContainsKey(sym.name)) symbols[sym.name] = new SymbolNode(sym);
+                v_left.Add(symbols[sym.name]);
+            }
+
+            foreach (Symbol sym in right)
+            {
+                if (!symbols.ContainsKey(sym.name)) symbols[sym.name] = new SymbolNode(sym);
+                v_right.Add(symbols[sym.name]);
+            }
+
+            List<Edge> assigns = new List<Edge>();
+
+            for (int i = 0; i < v_left.Count; i++) assigns.Add(new Edge(v_right[i], v_left[i], i));
+
+
+            assign_first.AddRange(moved_first);
+            foreach(var assign in assign_last)
+                moved_last.AddLast(assign);
+            
+            assign_last = moved_last.ToList();
+
+            var graph = new AssignGraph(assigns);
+            graph.assignFirst = assign_first;
+            graph.assignLast = assign_last;
+            return graph;
+        }
+        
+
+
+
+        private static List<Edge> make2n(List<Symbol> left, List<Symbol> right)
+        {
+            var temps = new List<SymbolNode>();
+            var res = new List<Edge>();
+            
+            for(int i = 0; i < right.Count; i++)
+            {
+                var to = new SymbolNode(new TempSymbol());
+                var from = new SymbolNode(right[i]); 
+                temps.Add(to);
+                res.Add(new Edge(from, to));
+            }
+
+            
+            for (int i = 0; i < left.Count; i++)
+            {
+                var to = new SymbolNode(left[i]);
+                res.Add(new Edge(temps[i], to));
+            }
+            return res;
+        }
+
+        private static AssignGraph createReversedGraph(this AssignGraph g)
+        {
+            List<Edge> newEdges = new List<Edge>();
+            foreach (var edge in g.edges)
+            {
+                newEdges.Add(new Edge(f: edge.to, t: edge.from));
+            }
+
+            return new AssignGraph(newEdges, g.vertexes.ToList());
+        }
+
+        public static List<List<SymbolNode>> findStronglyConnectedComponets(this AssignGraph g)
+        {
+            List<List<SymbolNode>> res = new List<List<SymbolNode>>();
+
+            Stack<SymbolNode> route = new Stack<SymbolNode>();
+            HashSet<SymbolNode> visited = new HashSet<SymbolNode>();
+
+            Action<AssignGraph> onEnterGraph = (_) =>
+            {
+                route.Clear();
+                visited.Clear();
+            };
+
+            Action<AssignGraph, SymbolNode> onEnterNode = (graph, node) => { visited.Add(node); };
+
+            Action<AssignGraph, SymbolNode> onLeaveNode = (graph, node) => { route.Push(node); };
+
+            Func<AssignGraph, SymbolNode, SymbolNode, bool> onProcessChildNode = (graph, parent, childNode) =>
+            {
+                if (!visited.Contains(childNode))
+                {
+                    return true;
+                }
+                else return false;
+            };
+
+            Func<AssignGraph, SymbolNode, bool> onProcessVertex = (graph, vert) => { return !visited.Contains(vert); };
+
+            g.dfs(OnEnterGraph: onEnterGraph, OnProcessVertex: onProcessVertex,
+                OnEnterNode: onEnterNode, OnProcessNodeChild: onProcessChildNode,
+                OnLeaveNode: onLeaveNode,
+                OnLeaveGraph: (_) => { }
+            );
+
+            Action<AssignGraph> onEnterGraphReversed = (_) => { visited.Clear(); };
+
+            Action<AssignGraph, SymbolNode> onEnterNodeReversed = (graph, node) =>
+            {
+                visited.Add(node);
+                res.Last().Add(node);
+            };
+
+            Action<AssignGraph, SymbolNode> onLeaveNodeReversed = (graph, node) => { };
+
+            Func<AssignGraph, SymbolNode, SymbolNode, bool> onProcessChildNodeReversed = (graph, parent, childNode) =>
+            {
+                if (!visited.Contains(childNode))
+                {
+                    return true;
+                }
+                else return false;
+            };
+
+            Func<AssignGraph, SymbolNode, bool> onProcessVertexReversed = (graph, vert) =>
+            {
+                if (visited.Contains(vert)) return false;
+                else
+                {
+                    res.Add(new List<SymbolNode>());
+                    return true;
+                }
+            };
+
+            var graphTraversalOrder = route.ToList();
+
+            var g_rev = g.createReversedGraph();
+
+            g_rev.dfs(OnEnterGraph: onEnterGraphReversed, OnProcessVertex: onProcessVertexReversed,
+                OnEnterNode: onEnterNodeReversed, OnProcessNodeChild: onProcessChildNodeReversed,
+                OnLeaveNode: onLeaveNodeReversed,
+                OnLeaveGraph: (_) => { },
+                graphTraversalOrder: graphTraversalOrder);
+
+            return res;
+        }
+
+        public static List<Cycle> findAllUniqueElementaryCycles(this AssignGraph g)
+        {
+            var res = new List<Cycle>();
+            var components = g.findStronglyConnectedComponets();
+            foreach (var component in components)
+            {
+                if (component.Count() > 1) res.Add(new Cycle(component));
+            }
+            return res;
+        }
+
+        public static void LogGraph(this AssignGraph graph)
+        {
+            foreach (var vert in graph.vertexes)
+            {
+                Console.Write("{0}->[", vert);
+                graph.OutAdjStructure[vert].ForEach(v => Console.Write("{0}, ", v));
+                Console.WriteLine("]");
+            }
+        }
+ 
+        public static void drawGraph(this AssignGraph g)
+        {
+            var writer = File.CreateText("graph.dot");
+            writer.WriteLine("digraph _graph {");
+
+            Action<AssignGraph> enterGraph = (graph) => { graph.resetVertexesColor(); };
+
+            Func<AssignGraph, SymbolNode, bool> ProcessNode = (graph, node) => node.color != SymbolNode.Color.GREY;
+
+            Action<AssignGraph, SymbolNode> EnterNode = (graph, vert) => { vert.color = SymbolNode.Color.GREY; };
+
+            Func<AssignGraph, SymbolNode, SymbolNode, bool> ProcessNodeChild = (graph, parent, child) =>
+            {
+                writer.WriteLine(parent.label + "->" + child.label);
+                return child.color == SymbolNode.Color.WHITE;
+            };
+
+            g.dfs(OnEnterGraph: enterGraph, OnEnterNode: EnterNode, OnProcessNodeChild: ProcessNodeChild,
+                OnProcessVertex: ProcessNode, OnLeaveGraph: (graph) => { graph.resetVertexesColor(); }, OnLeaveNode: (graph, vertex) => { });
+            writer.WriteLine("}");
+            writer.Close();
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/Symbol.cs

@@ -0,0 +1,133 @@
+using System.Collections.Generic;
+using System.Diagnostics;
+using PascalABCCompiler.SyntaxTree;
+
+namespace AssignTupleDesugarAlgorithm
+{
+    public class Symbol
+    {
+        public enum Type
+        {
+            VAR_PARAM, FROM_OUTER_SCOPE, INDEXER, DOT_NODE, LOCAL, EXPR, POINTER, CONST_EXPR
+        }
+        public string name;
+        public string last_name;
+
+        //public bool canBeSynonym = false;
+        //public bool isIndexer = false;
+        //public bool isExpr = false;
+        public expression node;
+        public Type type;
+
+        public Symbol(expression ex, BindCollectLightSymInfo binder)
+        {
+            node = ex;
+            if (node is indexer ind)
+            {
+                name = ind.ToString();
+                last_name = name;
+                type = Type.INDEXER;
+            }
+            else if (node is dot_node dn)
+            {
+                var last = dn.right;
+                while (last is dot_node dn1)
+                    last = dn1.right;
+
+                name = node.ToString();
+                last_name = last.ToString();
+                type = Type.DOT_NODE;
+                if (last is indexer)
+                    type = Type.INDEXER;
+            }
+            else if (node is ident id)
+            {
+                name = id.name;
+                last_name = name;
+                if (binder != null)
+                {
+                    var info = binder.bind(id);
+                    if (isVarParam(info))
+                    {
+                        type = Type.VAR_PARAM;
+                    }
+                    else if (isFromOuterScope(info))
+                    {
+                        type = Type.FROM_OUTER_SCOPE;
+                    }
+                    else
+                    {
+                        type = Type.LOCAL;
+                    }
+                }
+            }
+
+            else if (node is get_address || node is roof_dereference)
+            {
+                type = Type.POINTER;
+            }
+            else if(node is const_node)
+            {
+                type = Type.CONST_EXPR;
+            }
+            else
+            {
+                type = Type.EXPR;
+                name = node.ToString();
+                last_name = name;
+            }
+        }
+
+        public bool StructurallyEquals(Symbol sym) => node.ToString() == sym.node.ToString();
+
+        public override bool Equals(object obj)
+        {
+            if (obj is null) return false;
+            if (obj.GetType() != GetType()) return false;
+            return name == (obj as Symbol).name;
+        }
+
+        public override int GetHashCode()
+        {
+            return 363513814 + EqualityComparer<string>.Default.GetHashCode(name);
+        }
+
+
+        static bool isFromOuterScope(BindResult bindRes)
+        {
+            var symbol = bindRes.symInfo;
+
+            if (symbol == null)
+                return true;
+
+            if (symbol.SK == SymKind.var && symbol.Attr.HasFlag(SymbolAttributes.varparam_attr))
+                return true;
+
+            if (bindRes.path[bindRes.path.Count - 1] is GlobalScopeSyntax)
+                return true;
+
+            for (var i = 0; i < bindRes.path.Count - 1; i++)
+                if (bindRes.path[i] is NamedScopeSyntax)
+                    return true;
+
+            return false;
+        }
+
+        static bool isVarParam(BindResult res)
+        {
+            if (res == null)
+                return true;
+            return res.symInfo.Attr.HasFlag(SymbolAttributes.varparam_attr);
+        }
+    }
+
+    public class TempSymbol : Symbol
+    {
+        private static int counter = 0;
+        private static string getTempPrefix => "<tup_opt>" + counter++;
+        public TempSymbol() : base(new ident(getTempPrefix), null)
+        {
+            type = Type.LOCAL;
+        }
+    }
+}

SyntaxVisitors/SugarVisitors/AssignTuplesDesugarVisitor/desugarAlgoritm/SymbolNode.cs

@@ -0,0 +1,67 @@
+using System;
+
+namespace AssignTupleDesugarAlgorithm
+{
+
+    internal class SymbolNode : IEquatable<SymbolNode>
+    {
+        public readonly string label;
+        public int? number = null;
+        public readonly Symbol symbol;
+
+        public SymbolNode(Symbol s)
+        {
+            symbol = s;
+            label = s.name;
+        }
+
+        public enum Color
+        {
+            WHITE,
+            GREY,
+            BLACK
+        }
+
+        public Color color = Color.WHITE;
+        public void resetColor() => color = Color.WHITE;
+
+        public bool Equals(SymbolNode other)
+        {
+            if (other is null) return false;
+
+            return label == other.label;
+        }
+
+        public override int GetHashCode()
+        {
+            return label.GetHashCode();
+        }
+
+        public override bool Equals(object other)
+        {
+            if (GetType() != other.GetType()) return false;
+            return Equals((SymbolNode)other);
+        }
+
+
+        public override string ToString()
+        {
+            string n = "";
+            if (number != null)
+            {
+                n = "(" + number.ToString() + ")";
+            }
+
+            return label + n;
+        }
+    }
+
+    internal class TempSymbolNode : SymbolNode
+    {
+        public TempSymbolNode(TempSymbol s) : base(s)
+        {
+
+        }
+    }
+
+}

SyntaxVisitors/SugarVisitors/TupleVisitor.cs

@@ -14,11 +14,14 @@ namespace SyntaxVisitors.SugarVisitors
     /// </summary>
     public class TupleVisitor : BaseChangeVisitor
     {
-        public static TupleVisitor New
+        public bool optimize_tuple_assign;
+
+        public TupleVisitor(bool optimize_tup_opt)
         {
-            get { return new TupleVisitor(); }
+            optimize_tuple_assign = optimize_tup_opt;
         }
 
+        public static TupleVisitor Create(bool optimize_tup_opt) => new TupleVisitor(optimize_tup_opt);
         private int num = 0;
         public string UniqueName()
         {
@@ -59,7 +62,9 @@ namespace SyntaxVisitors.SugarVisitors
         // Остальное раскрывается в AssignTuplesDesugarVisitor
         public override void visit(assign_var_tuple assvartup)
         {
-            if (assvartup.expr is tuple_node tn && tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
+            if (assvartup.expr is tuple_node tn)
+            {
+                if (tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
                 {
                     var n = assvartup.idents.idents.Count();
                     if (n > tn.el.Count)
@@ -77,15 +82,23 @@ namespace SyntaxVisitors.SugarVisitors
                     }
                     ReplaceStatementUsingParent(assvartup, sl);
                 }
+                else if (optimize_tuple_assign)
+                    return;
+                else
+                    DefaultVisit(assvartup);
+            }
             else
             {
                 DefaultVisit(assvartup);
             }
+            
         }
 
         public override void visit(assign_tuple asstup)
         {
-            if (asstup.expr is tuple_node tn && tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
+            if (asstup.expr is tuple_node tn)
+            {
+                if (tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
                 {
                     var n = asstup.vars.variables.Count();
                     if (n > tn.el.Count)
@@ -103,18 +116,20 @@ namespace SyntaxVisitors.SugarVisitors
                     }
                     ReplaceStatementUsingParent(asstup, sl);
                 }
-            else if (asstup.expr is tuple_node tn1 && !tn1.el.expressions.Any(ex => ex is nil_const))
+                else if (optimize_tuple_assign)
+                    return;
+                else if (!tn.el.expressions.Any(ex => ex is nil_const))
                 {
                     var n = asstup.vars.variables.Count();
-                if (n > tn1.el.Count)
+                    if (n > tn.el.Count)
                         throw new SyntaxVisitorError("TOO_MANY_ELEMENTS_ON_LEFT_SIDE_OF_TUPLE_ASSIGNMENT", asstup.vars.variables[0]);
 
                     var sl = new List<statement>();
                     for (var i = 0; i < n; i++)
                     {
-                    var temp_id = new ident(UniqueName(), tn1.el.expressions[i].source_context);
+                        var temp_id = new ident(UniqueName(), tn.el.expressions[i].source_context);
-                    var var_def = new var_def_statement(temp_id, tn1.el.expressions[i], tn1.el.expressions[i].source_context);
+                        var var_def = new var_def_statement(temp_id, tn.el.expressions[i], tn.el.expressions[i].source_context);
-                    var a = new var_statement(var_def, tn1.el.expressions[i].source_context);
+                        var a = new var_statement(var_def, tn.el.expressions[i].source_context);
                         sl.Add(a);
                     }
 
@@ -130,10 +145,14 @@ namespace SyntaxVisitors.SugarVisitors
 
                     ReplaceStatementUsingParent(asstup, sl);
                 }
+                else
+                    DefaultVisit(asstup);
+            }
             else
             {
                 DefaultVisit(asstup);
             }
+            
         }
 
         public void ReplaceVarTupleDefStatementUsingParent(var_tuple_def_statement from, IEnumerable<var_def_statement> to)
@@ -150,7 +169,8 @@ namespace SyntaxVisitors.SugarVisitors
         // А это по идее до begin - там немного другие узлы и внешний контекст
         public override void visit(var_tuple_def_statement vtd)
         {
-            if (vtd.inital_value is tuple_node tn && tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
+            if (vtd.inital_value is tuple_node tn) {
+                if (tn.el.expressions.All(ex => ex is const_node) && !tn.el.expressions.Any(ex => ex is nil_const))
                 {
                     var n = vtd.vars.idents.Count();
                     if (n > tn.el.Count)
@@ -167,10 +187,16 @@ namespace SyntaxVisitors.SugarVisitors
                     ReplaceVarTupleDefStatementUsingParent(vtd, vd);
                     visit(vtd.inital_value);
                 }
+                else if (optimize_tuple_assign)
+                    return;
+                else
+                    DefaultVisit(vtd);
+            }
             else
             {
                 DefaultVisit(vtd);
             }
+            
         }
 
         public override void visit(tuple_node tup)

SyntaxVisitors/SyntaxVisitors.csproj

@@ -52,6 +52,14 @@
     <Compile Include="LightSymInfoVisitors\CollectLightSymInfoVisitor.cs" />
     <Compile Include="LightSymInfoVisitors\LightScopeCreator.cs" />
     <Compile Include="LightSymInfoVisitors\LightScopeHelperClasses.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\Assign.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\AssignGraph.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\Cycle.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\Edge.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\GraphUtils.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\Symbol.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\desugarAlgoritm\SymbolNode.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\NewAssignTuplesDesugarVisitor.cs" />
     <Compile Include="SugarVisitors\CacheFunctionVisitor.cs" />
     <Compile Include="SugarVisitors\LetExprVisitor.cs" />
     <Compile Include="SugarVisitors\TestAssignIsDefVisitor.cs" />
@@ -65,7 +73,7 @@
     <Compile Include="PatternsVisitors\PatternsDesugaringVisitor.cs" />
     <Compile Include="PatternsVisitors\ReplaceNamesInIsVarVisitor.cs" />
     <Compile Include="PatternsVisitors\SingleDeconstructChecker.cs" />
-    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor.cs" />
+    <Compile Include="SugarVisitors\AssignTuplesDesugarVisitor\AssignTuplesDesugarVisitor.cs" />
     <Compile Include="SugarVisitors\DoubleQuestionDesugarVisitor.cs" />
     <Compile Include="SugarVisitors\IndexVisitor.cs" />
     <Compile Include="SugarVisitors\LoopDesugarVisitor.cs" />

SyntaxVisitors/YieldVisitors/RenameSameBlockLocalVarsVisitor.cs

@@ -113,13 +113,16 @@ namespace SyntaxVisitors
                 return;
             }
 
+            var newNameCache = new Dictionary<string, string>();
+
             var newLocalNames = var_def.vars.idents.Select(id => 
                 {
                     var low = id.name.ToLower();
 
                     var newName = this.CreateNewVariableName(low);
                     //BlockNamesStack[CurrentLevel].Add(low, newName);
-                    BlockNamesStack[CurrentLevel][low] = newName;
+                    //BlockNamesStack[CurrentLevel][low] = newName;
+                    newNameCache[low] = newName;
                     return new ident(newName, id.source_context);
                 });
 
@@ -130,6 +133,8 @@ namespace SyntaxVisitors
             Replace(var_def, newVS);
             listNodes[listNodes.Count - 1] = newVS; //SSM 8.11.18
             ProcessNode(newVS.inital_value); // SSM 10.06.2020 #2103
+            foreach (var key in newNameCache.Keys)
+                BlockNamesStack[CurrentLevel][key] = newNameCache[key];
             //base.visit(newVS); // SSM 10.06.2020 - зачем обходить всё?
         }
 

TestSuite/CompilationSamples/ABCObjects.pas

@@ -10,7 +10,6 @@ unit ABCObjects;
 //{$apptype windows}
 {$reference '%GAC%\System.Windows.Forms.dll'}
 {$reference '%GAC%\System.Drawing.dll'}
-{$gendoc true}
 
 interface
 

TestSuite/CompilationSamples/CRT.pas

@@ -7,7 +7,6 @@
 unit CRT;
 
 {$apptype console}
-{$gendoc true}
 
 interface
 

TestSuite/CompilationSamples/GraphABC.pas

@@ -8,7 +8,6 @@ unit GraphABC;
 {$apptype windows} 
 {$reference '%GAC%\System.Windows.Forms.dll'}
 {$reference '%GAC%\System.Drawing.dll'}
-{$gendoc true}
 
 interface
 

TestSuite/CompilationSamples/PABCSystem.pas

@@ -7,8 +7,6 @@ unit PABCSystem;
 
 {$zerobasedstrings off}
 
-{$gendoc true}
-
 // Default Application type
 {$apptype console}
 
@@ -1432,24 +1430,26 @@ function ParamStr(i: integer): string;
 /// Возвращает текущий каталог
 function GetDir: string;
 /// Меняет текущий каталог
-procedure ChDir(s: string);
+procedure ChDir(dirName: string);
 /// Создает каталог
-procedure MkDir(s: string);
+procedure MkDir(dirName: string);
 /// Удаляет каталог
-procedure RmDir(s: string);
+procedure RmDir(dirName: string);
 
 /// Создает каталог. Возвращает True, если каталог успешно создан
-function CreateDir(s: string): boolean;
+function CreateDir(dirName: string): boolean;
 /// Удаляет файл. Если файл не может быть удален, то возвращает False
-function DeleteFile(fname: string): boolean;
+function DeleteFile(fileName: string): boolean;
 /// Возвращает текущий каталог
 function GetCurrentDir: string;
 /// Удаляет каталог. Возвращает True, если каталог успешно удален
-function RemoveDir(s: string): boolean;
+function RemoveDir(dirName: string): boolean;
 /// Переименовывает файл fileName, давая ему новое имя newfileName. Возвращает True, если файл успешно переименован
 function RenameFile(fileName, newfileName: string): boolean;
+/// Переименовывает каталог dirName, давая ему новое имя newDirName. Возвращает True, если каталог успешно переименован
+function RenameDirectory(dirName, newDirName: string): boolean;
 /// Устанавливает текущий каталог. Возвращает True, если каталог успешно удален
-function SetCurrentDir(s: string): boolean;
+function SetCurrentDir(dirName: string): boolean;
 
 /// Изменяет расширение файла с именем fileName на newExt
 function ChangeFileNameExtension(fileName, newExt: string): string;
@@ -1464,9 +1464,9 @@ procedure Assert(cond: boolean; sourceFile: string := ''; line: integer := 0);
 procedure Assert(cond: boolean; message: string; sourceFile: string := ''; line: integer := 0);
 
 /// Возвращает свободное место в байтах на диске с именем diskname
-function DiskFree(diskname: string): int64;
+function DiskFree(diskName: string): int64;
 /// Возвращает размер в байтах на диске с именем diskname
-function DiskSize(diskname: string): int64;
+function DiskSize(diskName: string): int64;
 /// Возвращает свободное место в байтах на диске disk. disk=0 - текущий диск, disk=1 - диск A: , disk=2 - диск B: и т.д.
 function DiskFree(disk: integer): int64;
 /// Возвращает размер в байтах на диске disk. disk=0 - текущий диск, disk=1 - диск A: , disk=2 - диск B: и т.д.
@@ -8461,41 +8461,41 @@ begin
   Result := Environment.CurrentDirectory;
 end;
 
-procedure ChDir(s: string);
+procedure ChDir(dirName: string);
 begin
-  Environment.CurrentDirectory := s;
+  Environment.CurrentDirectory := dirName;
 end;
 
-procedure MkDir(s: string);
+procedure MkDir(dirName: string);
 begin
-  Directory.CreateDirectory(s);
+  Directory.CreateDirectory(dirName);
 end;
 
-procedure RmDir(s: string);
+procedure RmDir(dirName: string);
 begin
-  Directory.Delete(s);
+  Directory.Delete(dirName);
 end;
 
-function CreateDir(s: string): boolean;
+function CreateDir(dirName: string): boolean;
 begin
   try
     Result := True;
-    Directory.CreateDirectory(s);
+    Directory.CreateDirectory(dirName);
   except
     Result := False;
   end;
 end;
 
-function DeleteFile(fname: string): boolean;
+function DeleteFile(fileName: string): boolean;
 begin
-  if not &File.Exists(fname) then
+  if not &File.Exists(fileName) then
   begin
     Result := False;
     exit
   end;
   try
     Result := True;
-    &File.Delete(fname);
+    &File.Delete(fileName);
   except
     Result := False;
   end;
@@ -8506,11 +8506,11 @@ begin
   Result := Environment.CurrentDirectory;
 end;
 
-function RemoveDir(s: string): boolean;
+function RemoveDir(dirName: string): boolean;
 begin
   try
     Result := True;
-    Directory.Delete(s);
+    Directory.Delete(dirName);
   except
     Result := False;
   end;
@@ -8526,11 +8526,21 @@ begin
   end;
 end;
 
-function SetCurrentDir(s: string): boolean;
+function RenameDirectory(dirName, newDirName: string): boolean;
 begin
   try
     Result := True;
-    Environment.CurrentDirectory := s;
+    Directory.Move(dirName, newDirName);
+  except
+    Result := False;
+  end;
+end;
+
+function SetCurrentDir(dirName: string): boolean;
+begin
+  try
+    Result := True;
+    Environment.CurrentDirectory := dirName;
   except
     Result := False;
   end;
@@ -8598,7 +8608,7 @@ begin
     System.Diagnostics.Contracts.Contract.Assert(cond,'Файл '+sourceFile+', строка '+line.ToString() + ': ' + message)
 end;
 
-function DiskFree(diskname: string): int64;
+function DiskFree(diskName: string): int64;
 begin
   try
     var d := new System.IO.DriveInfo(diskname);
@@ -8608,7 +8618,7 @@ begin
   end;
 end;
 
-function DiskSize(diskname: string): int64;
+function DiskSize(diskName: string): int64;
 begin
   try
     var d := new System.IO.DriveInfo(diskname);
@@ -13745,6 +13755,23 @@ begin
   Result := Self.Split(delims.ToCharArray, System.StringSplitOptions.RemoveEmptyEntries);
 end;
 
+/// Преобразует многострочную строку в массив строк
+function ToLines(Self: string): array of string; extensionmethod;
+begin
+  Result := Self.Split(|
+    #13#10, // CR+LF: Win
+    #10, // LF: Linux
+    #13 // CR: Mac
+    // https://en.m.wikipedia.org/wiki/Newline#Unicode
+    // But standard .Net things like System.IO.StringReader don't support these, so for now - commented out
+//    #11, // Vertical Tab
+//    #12, // Form feed
+//    char($85), // Next Line
+//    char($2028), // Line Separator
+//    char($2029), // Paragraph SeparatorS
+  |, System.StringSplitOptions.None);
+end;
+
 procedure PassSpaces(var s: string; var from: integer); 
 begin
   while (from <= s.Length) and char.IsWhiteSpace(s[from]) do

TestSuite/errors/err0538.pas

@@ -0,0 +1,8 @@
+//!Повторно объявленный идентификатор name
+type
+  name = (name);
+
+begin
+  // Ожидался тип
+  var v1: name;
+end.

TestSuite/errors/err0539.pas

@@ -0,0 +1,11 @@
+//!Количество полей не совпадает с количеством полей в записи
+type
+  r1 = record
+    a: byte;
+    static b: word;
+  end;
+  
+begin
+  // Работает, но не должно
+  var a: r1 := (a: 1; b: 2);
+end.

TestSuite/recinit3.pas

@@ -0,0 +1,11 @@
+type
+  r1 = record
+    a: byte;
+    static b: word;
+  end;
+  
+begin
+  //Ошибка: Количество полей не совпадает с количеством полей в записи
+  var a: r1 := (a: 1);
+  assert(a.a = 1);
+end.

TestSuite/units/u_events6.pas

@@ -0,0 +1,10 @@
+unit u_events6;
+
+uses System;
+
+type
+  I1 = interface 
+    event E1: Action;
+  end;
+
+end.

TestSuite/usesunits/use_events6.pas

@@ -0,0 +1,20 @@
+uses u_events6, System;
+
+type TClass = class(I1)
+  event E1: Action;
+  
+  procedure RaiseMethod;
+  begin
+    if E1 <> nil then
+      E1();
+  end;
+
+end;
+
+begin
+  var i := 0;
+  var o := new TClass;
+  o.E1 += () -> begin Inc(i) end;
+  o.RaiseMethod();
+  assert(i = 1);
+end.

TestSuite/yield8.pas

@@ -0,0 +1,29 @@
+function V(n: byte) := 1;
+
+function f1: sequence of integer;
+begin
+  //Ошибка: Ожидалось имя процедуры или функции
+  var v := V(0);
+  // Если закомментировать эту строчку - предыдущая строчка работает
+  yield v;
+end;
+
+function f2: sequence of integer;
+begin
+  //Ошибка: Ожидалось имя процедуры или функции
+  var v := V(0);
+  var w := v + 1;
+  // Если закомментировать эту строчку - предыдущая строчка работает
+  yield w;
+end;
+
+begin
+  var i := 0;
+  foreach var j in f1 do
+    i := j;
+  assert(i = 1);
+  
+  foreach var j in f2 do
+    i := j;
+  assert(i = 2);
+end.

TreeConverter/TreeConversion/syntax_tree_visitor.cs

@@ -12211,6 +12211,8 @@ namespace PascalABCCompiler.TreeConverter
                 context.check_name_free(name, loc);
                 is_direct_type_decl = true;
                 type_node tn = convert_strong(_type_declaration.type_def);
+                if (_type_declaration.type_def is enum_type_definition)
+                    context.check_name_free(name, loc);
                 assign_doc_info(tn,_type_declaration);
                 is_direct_type_decl = false;
                 if (_type_declaration.type_def is SyntaxTree.named_type_reference||
@@ -15595,13 +15597,14 @@ namespace PascalABCCompiler.TreeConverter
         private record_initializer ConvertRecordInitializer(common_type_node ctn, record_initializer constant)
         {
         	location loc = constant.location;
+            var non_static_fields = ctn.fields.Where(x => !x.IsStatic).ToArray();
             if (!ctn.is_value_type)
                 AddError(loc, "RECORD_CONST_NOT_ALLOWED_{0}", ctn.name);
-            if (ctn.fields.Count != constant.record_const_definition_list.Count)
+            if (non_static_fields.Length != constant.record_const_definition_list.Count)
                 AddError(loc, "INVALID_RECORD_CONST_FIELD_COUNT");
             constant.type = ctn;
             constant.field_values.Clear();
-            for (int i = 0; i < ctn.fields.Count; i++)
+            for (int i = 0; i < non_static_fields.Length; i++)
             {
                 class_field cf = ctn.fields[i];
                 if (cf.name.ToLower() != constant.record_const_definition_list[i].name.name.ToLower())

bin/Lib/PABCSystem.pas

@@ -1430,24 +1430,26 @@ function ParamStr(i: integer): string;
 /// Возвращает текущий каталог
 function GetDir: string;
 /// Меняет текущий каталог
-procedure ChDir(s: string);
+procedure ChDir(dirName: string);
 /// Создает каталог
-procedure MkDir(s: string);
+procedure MkDir(dirName: string);
 /// Удаляет каталог
-procedure RmDir(s: string);
+procedure RmDir(dirName: string);
 
 /// Создает каталог. Возвращает True, если каталог успешно создан
-function CreateDir(s: string): boolean;
+function CreateDir(dirName: string): boolean;
 /// Удаляет файл. Если файл не может быть удален, то возвращает False
-function DeleteFile(fname: string): boolean;
+function DeleteFile(fileName: string): boolean;
 /// Возвращает текущий каталог
 function GetCurrentDir: string;
 /// Удаляет каталог. Возвращает True, если каталог успешно удален
-function RemoveDir(s: string): boolean;
+function RemoveDir(dirName: string): boolean;
 /// Переименовывает файл fileName, давая ему новое имя newfileName. Возвращает True, если файл успешно переименован
 function RenameFile(fileName, newfileName: string): boolean;
+/// Переименовывает каталог dirName, давая ему новое имя newDirName. Возвращает True, если каталог успешно переименован
+function RenameDirectory(dirName, newDirName: string): boolean;
 /// Устанавливает текущий каталог. Возвращает True, если каталог успешно удален
-function SetCurrentDir(s: string): boolean;
+function SetCurrentDir(dirName: string): boolean;
 
 /// Изменяет расширение файла с именем fileName на newExt
 function ChangeFileNameExtension(fileName, newExt: string): string;
@@ -1462,9 +1464,9 @@ procedure Assert(cond: boolean; sourceFile: string := ''; line: integer := 0);
 procedure Assert(cond: boolean; message: string; sourceFile: string := ''; line: integer := 0);
 
 /// Возвращает свободное место в байтах на диске с именем diskname
-function DiskFree(diskname: string): int64;
+function DiskFree(diskName: string): int64;
 /// Возвращает размер в байтах на диске с именем diskname
-function DiskSize(diskname: string): int64;
+function DiskSize(diskName: string): int64;
 /// Возвращает свободное место в байтах на диске disk. disk=0 - текущий диск, disk=1 - диск A: , disk=2 - диск B: и т.д.
 function DiskFree(disk: integer): int64;
 /// Возвращает размер в байтах на диске disk. disk=0 - текущий диск, disk=1 - диск A: , disk=2 - диск B: и т.д.
@@ -8459,41 +8461,41 @@ begin
   Result := Environment.CurrentDirectory;
 end;
 
-procedure ChDir(s: string);
+procedure ChDir(dirName: string);
 begin
-  Environment.CurrentDirectory := s;
+  Environment.CurrentDirectory := dirName;
 end;
 
-procedure MkDir(s: string);
+procedure MkDir(dirName: string);
 begin
-  Directory.CreateDirectory(s);
+  Directory.CreateDirectory(dirName);
 end;
 
-procedure RmDir(s: string);
+procedure RmDir(dirName: string);
 begin
-  Directory.Delete(s);
+  Directory.Delete(dirName);
 end;
 
-function CreateDir(s: string): boolean;
+function CreateDir(dirName: string): boolean;
 begin
   try
     Result := True;
-    Directory.CreateDirectory(s);
+    Directory.CreateDirectory(dirName);
   except
     Result := False;
   end;
 end;
 
-function DeleteFile(fname: string): boolean;
+function DeleteFile(fileName: string): boolean;
 begin
-  if not &File.Exists(fname) then
+  if not &File.Exists(fileName) then
   begin
     Result := False;
     exit
   end;
   try
     Result := True;
-    &File.Delete(fname);
+    &File.Delete(fileName);
   except
     Result := False;
   end;
@@ -8504,11 +8506,11 @@ begin
   Result := Environment.CurrentDirectory;
 end;
 
-function RemoveDir(s: string): boolean;
+function RemoveDir(dirName: string): boolean;
 begin
   try
     Result := True;
-    Directory.Delete(s);
+    Directory.Delete(dirName);
   except
     Result := False;
   end;
@@ -8524,11 +8526,21 @@ begin
   end;
 end;
 
-function SetCurrentDir(s: string): boolean;
+function RenameDirectory(dirName, newDirName: string): boolean;
 begin
   try
     Result := True;
-    Environment.CurrentDirectory := s;
+    Directory.Move(dirName, newDirName);
+  except
+    Result := False;
+  end;
+end;
+
+function SetCurrentDir(dirName: string): boolean;
+begin
+  try
+    Result := True;
+    Environment.CurrentDirectory := dirName;
   except
     Result := False;
   end;
@@ -8596,7 +8608,7 @@ begin
     System.Diagnostics.Contracts.Contract.Assert(cond,'Файл '+sourceFile+', строка '+line.ToString() + ': ' + message)
 end;
 
-function DiskFree(diskname: string): int64;
+function DiskFree(diskName: string): int64;
 begin
   try
     var d := new System.IO.DriveInfo(diskname);
@@ -8606,7 +8618,7 @@ begin
   end;
 end;
 
-function DiskSize(diskname: string): int64;
+function DiskSize(diskName: string): int64;
 begin
   try
     var d := new System.IO.DriveInfo(diskname);
@@ -13743,6 +13755,23 @@ begin
   Result := Self.Split(delims.ToCharArray, System.StringSplitOptions.RemoveEmptyEntries);
 end;
 
+/// Преобразует многострочную строку в массив строк
+function ToLines(Self: string): array of string; extensionmethod;
+begin
+  Result := Self.Split(|
+    #13#10, // CR+LF: Win
+    #10, // LF: Linux
+    #13 // CR: Mac
+    // https://en.m.wikipedia.org/wiki/Newline#Unicode
+    // But standard .Net things like System.IO.StringReader don't support these, so for now - commented out
+//    #11, // Vertical Tab
+//    #12, // Form feed
+//    char($85), // Next Line
+//    char($2028), // Line Separator
+//    char($2029), // Paragraph SeparatorS
+  |, System.StringSplitOptions.None);
+end;
+
 procedure PassSpaces(var s: string; var from: integer); 
 begin
   while (from <= s.Length) and char.IsWhiteSpace(s[from]) do