add single ir generator methods

src/StgSharp.RegularAnalysis/Text/TextRegexSourceGen.GenClass.cs

@@ -72,9 +72,9 @@ namespace StgSharp.RegularAnalysis.Text
          * lives in test/SingleFile/regex.cs.
          */
 
-        private const string current_ptr = "cur_ptr_global";
-        private const string offset = "offset";
-        private const string orig_text = "text";
+        // private const string current_ptr = "cur_ptr_global";                // global match cursor
+        // private const string offset = "offset";                             // 
+        // private const string orig_text = "text";                            // 
 
         #region L0 method level
 
@@ -155,10 +155,11 @@ namespace StgSharp.RegularAnalysis.Text
                       .AppendLine($@"int region_{i}_end = -1;")
                       .AppendLine($@"bool region_{i}_success;");
             }
-
+            /*
             _ = se.AppendLine($@"int {current_ptr} = 0;")
                   .AppendLine($@"int {offset} = 0;")
                   .AppendLine();
+            /**/
 
             // _ = sc.GenVarDefine(se);
 
@@ -177,6 +178,14 @@ namespace StgSharp.RegularAnalysis.Text
 
             #endregion
 
+        private enum RegionExitMethod
+        {
+
+            Break,
+            Continue
+
+        }
+
         #region shared helpers
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -224,14 +233,14 @@ namespace StgSharp.RegularAnalysis.Text
 
         }
 
-        internal record struct RegexCharSet(
-                               string Value,
-                               CharSetType Type,
-                               bool Accept
+        internal record class RegexCharSet(
+                              string Value,
+                              CharSetType Type,
+                              bool Accept
         )
         {
 
-            public override readonly string ToString()
+            public override string ToString()
             {
                 return $"{{value:{Value}, type:{Type}, accept:{Accept}}}";
             }
@@ -244,34 +253,45 @@ namespace StgSharp.RegularAnalysis.Text
         )
         {
             // range or single
+            HashSet<char> single_char = [];
             if (source[0] == '[')
             {
                 int idx;
                 accept = source[1] != '^';
                 idx = accept ? 1 : 2;
+                List<RegexCharSet> list = [];
                 ReadOnlySpan<char> seq = source.Slice(idx, source.Length - idx - 1);
                 if (seq.IndexOf('-') == -1)
                 {
-                    return [new RegexCharSet(seq.ToString(), CharSetType.Single, true)];
+                    SplitSet(single_char, seq, list);
+                    StringBuilder sb = new();
+                    foreach (char c in single_char) {
+                        _ = sb.Append(c);
+                    }
+                    list.Add(new(sb.ToString(), CharSetType.Single, true));
                 } else
                 {
-                    List<RegexCharSet> list = [];
                     for (; seq.Length > 0; )
                     {
                         int pos = seq.IndexOf('-');
                         if (pos == -1)
                         {
                             // has no range
-                            SplitSet(seq, list);
+                            SplitSet(single_char, seq, list);
                             break;
                         } else if (pos > 1)
                         {
                             // has other sequence before range
-                            SplitSet(seq[0..(pos - 1)], list);
+                            SplitSet(single_char, seq[0..(pos - 1)], list);
                         }
                         list.Add(new($"{seq[pos - 1]}{seq[pos + 1]}", CharSetType.Range, true));
                         seq = seq[(pos + 2)..];
                     }
+                    StringBuilder sb = new();
+                    foreach (char c in single_char) {
+                        _ = sb.Append(c);
+                    }
+                    list.Add(new(sb.ToString(), CharSetType.Single, true));
                     return [.. list];
                 }
             } else if (source[0] == '\\')
@@ -293,6 +313,7 @@ namespace StgSharp.RegularAnalysis.Text
             }
 
             static void SplitSet(
+                        HashSet<char> single_char,
                         ReadOnlySpan<char> seq,
                         List<RegexCharSet> sets
             )
@@ -310,19 +331,31 @@ namespace StgSharp.RegularAnalysis.Text
                         sets.Add(new RegexCharSet(singles.ToString(), CharSetType.Single, true));
                     }
                     bool accept = char.IsAsciiLetterUpper(remain[pos + 1]);
-                    RegexCharSet set_set = char.ToLower(remain[pos + 1], CultureInfo.InvariantCulture)
-                        switch
+
+                    switch (char.ToLower(remain[pos + 1], CultureInfo.InvariantCulture))
                     {
-                        's' => new("s", CharSetType.Set, accept),
-                        'w' => new("w", CharSetType.Set, accept),
-                        'd' => new("d", CharSetType.Set, accept),
-                        _ => throw new NotSupportedException()
-                    };
-                    sets.Add(set_set);
+                        case 's':
+                            sets.Add(new("s", CharSetType.Set, accept));
+                            break;
+                        case 'w':
+                            sets.Add(new("w", CharSetType.Set, accept));
+                            break;
+                        case 'd':
+                            sets.Add(new("d", CharSetType.Set, accept));
+                            break;
+                        case '['or'('or')'or']'or'\\'or'\"':
+                            _ = single_char.Add(remain[pos + 1]);
+                            break;
+                        default:
+                            throw new InvalidCastException($"Unknown char or charset {remain[0..1]}");
+                    }
                     remain = remain[(pos + 2)..];
                 }
-                if (remain.Length > 0) {
-                    sets.Add(new RegexCharSet(remain.ToString(), CharSetType.Single, true));
+                if (remain.Length > 0)
+                {
+                    foreach (char c in remain) {
+                        _ = single_char.Add(c);
+                    }
                 }
             }
         }