fix errors in interpreter. add a enumerator for tree. working on tree optimizer

StgSharp.RegularAnalysis/Abstraction/AbstractSyntaxTree.cs

@@ -33,6 +33,7 @@ using System.Collections.Generic;
 using System.Runtime.CompilerServices;
 using System.Security.Cryptography.X509Certificates;
 using System.Text;
+using System.Xml.Linq;
 using System.Xml.Schema;
 
 namespace StgSharp.RegularAnalysis.Abstraction
@@ -81,26 +82,29 @@ namespace StgSharp.RegularAnalysis.Abstraction
 
         public IEnumerator<TNode> GetEnumerator()
         {
-            return new Enumerator(this);
+            return new TreeEnumerator<TNode, TType>(this);
         }
 
-        private class Enumerator : IEnumerator<TNode>
+    }
+
+    internal class TreeEnumerator<TNode, TType>(
+                   TNode root
+    ) : IEnumerator<TNode> where TNode : ISyntaxNode<TNode, TType> where TType : unmanaged
     {
 
+        private bool _completed = false;
+
         private int _state, _target; // 0: not started, 1: on right, 2: ended
-            private Stack<Record> _recycle;
+        private Stack<Record> _recycle = [];
-            private Stack<Record> _stack;
+        private Stack<Record> _stack = [];
-            private TNode _lRoot;
-            private TNode _root;
 
-            public Enumerator(
+        // private TNode _lRoot;
+        private TNode _root = root;
+
+        internal TreeEnumerator(
                  AbstractSyntaxTree<TNode, TType> tree
         )
-            {
+            : this(tree.Root) { }
-                _root = tree.Root;
-                _stack = [];
-                _recycle = [];
-            }
 
         public TNode Current
         {
@@ -120,6 +124,9 @@ namespace StgSharp.RegularAnalysis.Abstraction
 
         public bool MoveNext()
         {
+            if (_completed) {
+                return false;
+            }
             while (_stack.TryPeek(out Record? cur))
             {
                 switch (cur.State)
@@ -148,7 +155,9 @@ namespace StgSharp.RegularAnalysis.Abstraction
                         if (TNode.IsNullOrEmpty(cur.Node.Next))
                         {
                             _recycle.Push(_stack.Pop());
-                                if (_stack.Count == 0) {
+                            if (_stack.Count == 0)
+                            {
+                                _completed = true;
                                 return false;
                             }
                         } else
@@ -167,10 +176,50 @@ namespace StgSharp.RegularAnalysis.Abstraction
 
         public void Reset()
         {
+            _completed = false;
             _stack.Clear();
             _state = 0;
         }
 
+        public void SkipNode()
+        {
+            if (_stack.TryPop(out Record? r)) {
+                _recycle.Push(r);
+            }
+        }
+
+        public void SkipOnce()
+        {
+            if (_stack.TryPeek(out Record? cur))
+            {
+                switch (cur.State)
+                {
+                    case 0:
+                        cur.State++;
+                        break;
+                    case 1:
+                        cur.State++;
+                        break;
+                    case 2:
+                        if (TNode.IsNullOrEmpty(cur.Node.Next))
+                        {
+                            _recycle.Push(_stack.Pop());
+                            if (_stack.Count == 0)
+                            {
+                                _completed = true;
+                                return;
+                            }
+                        } else
+                        {
+                            _stack.Push(GetNewRecord(cur.Node.Next));
+                        }
+                        break;
+                    default:
+                        break;
+                }
+            }
+        }
+
         private Record GetNewRecord(
                        TNode node
         )
@@ -199,6 +248,4 @@ namespace StgSharp.RegularAnalysis.Abstraction
         }
 
     }
-
-    }
 }

StgSharp.RegularAnalysis/TextRegex/RegexInterpreter.Optimize.cs

@@ -0,0 +1,53 @@
+//-----------------------------------------------------------------------
+// -----------------------------------------------------------------------
+// file="RegexInterpreter.Optimize"
+// Project: StgSharp
+// AuthorGroup: Nitload
+// Copyright (c) Nitload. All rights reserved.
+//     
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//     
+// -----------------------------------------------------------------------
+// -----------------------------------------------------------------------
+using StgSharp.RegularAnalysis.Abstraction;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StgSharp.RegularAnalysis.TextRegex
+{
+    public partial class RegexInterpreter
+    {
+
+        private static RegexAstNode FlattenAlt(
+                                    RegexAstNode root
+        )
+        {
+            TreeEnumerator<RegexAstNode, RegexElementLabel> enumerator = new(root);
+            List<RegexAstNode> cases = [];
+            while (enumerator.MoveNext())
+            {
+                RegexAstNode current = enumerator.Current;
+            }
+        }
+
+    }
+}

StgSharp.RegularAnalysis/TextRegex/RegexInterpreter.cs

@@ -37,7 +37,7 @@ using System.Threading.Tasks;
 
 namespace StgSharp.RegularAnalysis.TextRegex
 {
-    public class RegexInterpreter
+    public partial class RegexInterpreter
     {
 
         private AbstractSyntaxTree<RegexAstNode, RegexElementLabel> _tree = new();
@@ -113,8 +113,11 @@ namespace StgSharp.RegularAnalysis.TextRegex
                     if (op.Source.Flag != RegexElementLabel.GROUP_BEGIN) {
                         throw new InvalidOperationException("Unmatched group begin and end symbol");
                     }
+                    if (op.Source.Value.Length > 1)
+                    {
                         op.Right = _stack.PopOperand();
                         _stack.PushOperand(op);
+                    }
                 } else if ((token.Flag & RegexElementLabel.OPERATOR) != 0)
                 {
                     Console.Write($"Operator {token.Value} with flag {token.Flag},  ");
@@ -179,27 +182,9 @@ namespace StgSharp.RegularAnalysis.TextRegex
                 RegexAstNode node = enumerator.Current;
                 if ((RegexElementLabel)node.NodeFlag == RegexElementLabel.ALT)
                 {
-                    RegexAstNode right, left = node.Left;
+                    RegexAstNode list = FlattenAlt(node);
-                    while (node.Right.Source.Flag == RegexElementLabel.ALT)
+                    node.Left = list;
-                    {
+                    node.Right = RegexAstNode.Empty;
-                        // flatten a alternation to left linked list of root ALT
-                        right = node.Right;
-                        RegexAstNode nextAlt = right.Left;
-                        left.Next = nextAlt;
-                        nextAlt.Previous = left;
-                        nextAlt.Parent = node;
-                        right.Left = RegexAstNode.Empty;
-                        left = nextAlt;
-
-                        // remove the right ALT node and connect its right child to current node
-                        node.Right = right.Right;
-                        right.Right.Parent = node;
-                    }
-
-                    // connect the last ALT node to the right child of current node
-                    right = node.Right;
-                    left.Next = right;
-                    right.Previous = left;
                 }
             }
 

StgSharpDebug/TestRegexAnalyse.cs

@@ -38,7 +38,7 @@ namespace StgSharp
     public class TestRegexAnalyse
     {
 
-        private const string regex = @"ab[1-9]+(?<name>abc)";
+        private const string regex = @"(ab[1-9])+(?<name>abc)";
 
         public static void Run()
         {