*** empty log message ***

diff --git a/MText.cs b/MText.cs
index ecc24eb..cff99d4 100644 (file)
--- a/MText.cs
+++ b/MText.cs
@@ -47,9 +47,9 @@ namespace M17N.Core
     private int cache_pos;
     private int cache_idx;
     private MTextPlist plist;
+    private bool unmodifiable;
 
     private static UTF8Encoding utf8 = new UTF8Encoding ();
-    private static UTF32Encoding utf32 = new UTF32Encoding (true, false);
 
     private static int count_chars (String str)
     {
@@ -111,74 +111,77 @@ namespace M17N.Core
       return (c >= 0xDC00 && c < 0xE000);
     }
 
-    private int inc_idx (int i)
+    private static int inc_idx (StringBuilder sb, int i)
     {
       return (i + (surrogate_high_p (sb[i]) ? 2 : 1));
     }
 
-    private int dec_idx (int i)
+    private static int dec_idx (StringBuilder sb, int i)
     {
       return (i - (surrogate_low_p (sb[i - 1]) ? 2 : 1));
     }
 
-    private int pos_to_idx (int pos)
+    private static int pos_to_idx (MText mt, int pos)
     {
+      if (pos == mt.cache_pos)
+       return mt.cache_idx;
+
       int p, i;
       bool forward;
 
-      if (pos < cache_pos)
+      if (pos < mt.cache_pos)
        {
-         if (cache_pos == cache_idx)
-           return cache_idx;
-         if (pos < cache_pos - pos)
+         if (mt.cache_pos == mt.cache_idx)
+           return mt.cache_idx;
+         if (pos < mt.cache_pos - pos)
            {
              p = i = 0;
              forward = true;
            }
          else
            {
-             p = cache_pos; i = cache_idx;
+             p = mt.cache_pos; i = mt.cache_idx;
              forward = false;
            }
        }
       else
        {
-         if (nchars - cache_pos == sb.Length - cache_idx)
-           return (cache_idx + pos - cache_pos);
-         if (pos - cache_pos < nchars - pos)
+         if (mt.nchars - mt.cache_pos == mt.sb.Length - mt.cache_idx)
+           return (mt.cache_idx + pos - mt.cache_pos);
+         if (pos - mt.cache_pos < mt.nchars - pos)
            {
-             p = cache_pos; i = cache_idx;
+             p = mt.cache_pos; i = mt.cache_idx;
              forward = true;
            }
          else
            {
-             p = nchars; i = sb.Length;
+             p = mt.nchars; i = mt.sb.Length;
              forward = false;
            }
        }
       if (forward)
-       for (; p < pos; i = inc_idx (i), p++);
+       for (; p < pos; i = inc_idx (mt.sb, i), p++);
       else
-       for (; p > pos; i = dec_idx (i), p--);
-      cache_pos = p;
-      cache_idx = i;
+       for (; p > pos; i = dec_idx (mt.sb, i), p--);
+      mt.cache_pos = p;
+      mt.cache_idx = i;
       return i;
     }
 
-    private readonly bool readonlyp;
-
     private void insert (int pos, MText mt2, int from, int to)
     {
-      if (pos != cache_pos)
-       pos = pos_to_idx (pos);
+      int pos_idx = pos_to_idx (this, pos);
+      int from_idx = pos_to_idx (mt2, from);
+      int to_idx = pos_to_idx (mt2, to);
 
+      sb.Insert (pos_idx, mt2.sb.ToString (from_idx, to_idx - from_idx));
+      nchars += to - from;
     }
 
     public int this[int i]
     {
       set {
-       if (i != cache_pos)
-         i = pos_to_idx (i);
+       i = pos_to_idx (this, i);
        if (value < 0x10000)
          sb[i] = (char) value;
        else
@@ -193,8 +196,7 @@ namespace M17N.Core
          }
       }
       get {
-       if (i != cache_pos)
-         i = pos_to_idx (i);
+       i = pos_to_idx (this, i);
        return (surrogate_high_p (sb[i])
                ? i = ((sb[i] - 0xD800) << 10) + (sb[i + 1] - 0xDC00) + 0x10000
                : sb[i]);
@@ -217,6 +219,15 @@ namespace M17N.Core
       insert (pos, mt, from, to);
       return this;
     }
+
+    public MText del (int from, int to)
+    {
+      sb.Remove (from, pos_to_idx (this, to) - pos_to_idx (this, from));
+      nchars -= to - from;
+      return this;
+    }
+
+
   }
 
   public class MTextProperty