diff --git a/qse/include/qse/awk/Awk.hpp b/qse/include/qse/awk/Awk.hpp
index f3fb0153..40c91d75 100644
--- a/qse/include/qse/awk/Awk.hpp
+++ b/qse/include/qse/awk/Awk.hpp
@@ -1,5 +1,5 @@
 /*
- * $Id: Awk.hpp 474 2011-05-23 16:52:37Z hyunghwan.chung $
+ * $Id: Awk.hpp 477 2011-05-24 04:22:40Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -412,20 +412,48 @@ public:
 		///
 		/// The Index class encapsulates an index of an arrayed value.
 		///
-		class Index
+		class Index: protected qse_cstr_t
 		{
 		public:
 			friend class Value;
 
 			/// The Index() function creates an empty array index.
-			Index (): ptr (EMPTY_STRING), len (0) {}
+			Index ()
+			{
+				this->ptr = EMPTY_STRING;
+				this->len = 0;
+			}
 
 			/// The Index() function creates a string array index.
-			Index (const char_t* ptr, size_t len):
-				ptr (ptr), len (len) {}
+			Index (const char_t* ptr, size_t len)
+			{
+				this->ptr = ptr;
+				this->len = len;
+			}
 
-			const char_t* ptr;
-			size_t        len;
+			void set (const qse_cstr_t* x)
+			{
+				this->ptr = x->ptr;
+				this->len = x->len;
+			}
+
+			void set (const qse_xstr_t* x)
+			{
+				this->ptr = x->ptr;
+				this->len = x->len;
+			}
+
+			Index& operator= (const qse_cstr_t* x)
+			{
+				this->set (x);
+				return *this;
+			}
+
+			Index& operator= (const qse_xstr_t* x)
+			{
+				this->set (x);
+				return *this;
+			}
 		};
 
 		///
diff --git a/qse/include/qse/awk/awk.h b/qse/include/qse/awk/awk.h
index b8ad85f0..c2d079bb 100644
--- a/qse/include/qse/awk/awk.h
+++ b/qse/include/qse/awk/awk.h
@@ -1,5 +1,5 @@
 /*
- * $Id: awk.h 474 2011-05-23 16:52:37Z hyunghwan.chung $
+ * $Id: awk.h 477 2011-05-24 04:22:40Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -274,10 +274,8 @@ struct qse_awk_val_map_itr_t
 };
 typedef struct qse_awk_val_map_itr_t qse_awk_val_map_itr_t;
 
-#define QSE_AWK_VAL_MAP_ITR_KEY_PTR(itr) \
-	((const qse_char_t*)QSE_HTB_KPTR((itr)->pair))
-#define QSE_AWK_VAL_MAP_ITR_KEY_LEN(itr) \
-	(*(const qse_size_t*)&QSE_HTB_KLEN((itr)->pair))
+#define QSE_AWK_VAL_MAP_ITR_KEY(itr) \
+	((const qse_cstr_t*)QSE_HTB_KPTL((itr)->pair))
 #define QSE_AWK_VAL_MAP_ITR_VAL(itr) \
 	((const qse_awk_val_t*)QSE_HTB_VPTR((itr)->pair))
 
diff --git a/qse/include/qse/cmn/htb.h b/qse/include/qse/cmn/htb.h
index fd4840e7..0ed56148 100644
--- a/qse/include/qse/cmn/htb.h
+++ b/qse/include/qse/cmn/htb.h
@@ -1,5 +1,5 @@
 /*
- * $Id: htb.h 474 2011-05-23 16:52:37Z hyunghwan.chung $
+ * $Id: htb.h 477 2011-05-24 04:22:40Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -285,6 +285,9 @@ struct qse_htb_t
 #define QSE_HTB_KSCALE(m) (*(const int*)&(m)->scale[QSE_HTB_KEY])
 #define QSE_HTB_VSCALE(m) (*(const int*)&(m)->scale[QSE_HTB_VAL])
 
+#define QSE_HTB_KPTL(p) (&(p)->key)
+#define QSE_HTB_VPTL(p) (&(p)->val)
+
 #define QSE_HTB_KPTR(p) ((p)->key.ptr)
 #define QSE_HTB_KLEN(p) ((p)->key.len)
 #define QSE_HTB_VPTR(p) ((p)->val.ptr)
diff --git a/qse/include/qse/cmn/map.h b/qse/include/qse/cmn/map.h
index 9b49aa54..11159fb1 100644
--- a/qse/include/qse/cmn/map.h
+++ b/qse/include/qse/cmn/map.h
@@ -79,6 +79,8 @@
 #	define QSE_MAP_KEEPER(map)                      QSE_HTB_KEEPER(map)
 #	define QSE_MAP_KSCALE(map)                      QSE_HTB_KSCALE(map) 
 #	define QSE_MAP_VSCALE(map)                      QSE_HTB_VSCALE(map) 
+#	define QSE_MAP_KPTL(p)                          QSE_HTB_KPTL(p)
+#	define QSE_MAP_VPTL(p)                          QSE_HTB_VPTL(p)
 #	define QSE_MAP_KPTR(p)                          QSE_HTB_KPTR(p)
 #	define QSE_MAP_KLEN(p)                          QSE_HTB_KLEN(p)
 #	define QSE_MAP_VPTR(p)                          QSE_HTB_VPTR(p)
@@ -135,6 +137,8 @@
 #	define QSE_MAP_KEEPER(map)                      QSE_RBT_KEEPER(map)
 #	define QSE_MAP_KSCALE(map)                      QSE_RBT_KSCALE(map) 
 #	define QSE_MAP_VSCALE(map)                      QSE_RBT_VSCALE(map) 
+#	define QSE_MAP_KPTL(p)                          QSE_RBT_KPTL(p)
+#	define QSE_MAP_VPTL(p)                          QSE_RBT_VPTL(p)
 #	define QSE_MAP_KPTR(p)                          QSE_RBT_KPTR(p)
 #	define QSE_MAP_KLEN(p)                          QSE_RBT_KLEN(p)
 #	define QSE_MAP_VPTR(p)                          QSE_RBT_VPTR(p)
diff --git a/qse/include/qse/cmn/rbt.h b/qse/include/qse/cmn/rbt.h
index 5bded784..febd986c 100644
--- a/qse/include/qse/cmn/rbt.h
+++ b/qse/include/qse/cmn/rbt.h
@@ -256,6 +256,9 @@ struct qse_rbt_t
 #define QSE_RBT_KSCALE(m) ((const int)(m)->scale[QSE_RBT_KEY])
 #define QSE_RBT_VSCALE(m) ((const int)(m)->scale[QSE_RBT_VAL])
 
+#define QSE_RBT_KPTL(p) (&(p)->key)
+#define QSE_RBT_VPTL(p) (&(p)->val)
+
 #define QSE_RBT_KPTR(p) ((p)->key.ptr)
 #define QSE_RBT_KLEN(p) ((p)->key.len)
 #define QSE_RBT_VPTR(p) ((p)->val.ptr)
diff --git a/qse/lib/awk/Awk.cpp b/qse/lib/awk/Awk.cpp
index e9cf405e..10aaf1b4 100644
--- a/qse/lib/awk/Awk.cpp
+++ b/qse/lib/awk/Awk.cpp
@@ -1,5 +1,5 @@
 /*
- * $Id: Awk.cpp 476 2011-05-23 17:07:13Z hyunghwan.chung $
+ * $Id: Awk.cpp 477 2011-05-24 04:22:40Z hyunghwan.chung $
  * 
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -806,8 +806,7 @@ Awk::Value::IndexIterator Awk::Value::getFirstIndex (Index* idx) const
 	iptr = qse_awk_rtx_getfirstmapvalitr (this->run->rtx, this->val, &itr);
 	if (iptr == QSE_NULL) return IndexIterator::END; // no more key
 
-	idx->ptr = QSE_AWK_VAL_MAP_ITR_KEY_PTR(iptr);
-	idx->len = QSE_AWK_VAL_MAP_ITR_KEY_LEN(iptr);
+	idx->set (QSE_AWK_VAL_MAP_ITR_KEY(iptr));
 
 	return itr;
 }
@@ -827,8 +826,7 @@ Awk::Value::IndexIterator Awk::Value::getNextIndex (
 	iptr = qse_awk_rtx_getnextmapvalitr (this->run->rtx, this->val, &itr);
 	if (iptr == QSE_NULL) return IndexIterator::END; // no more key
 
-	idx->ptr = QSE_AWK_VAL_MAP_ITR_KEY_PTR(iptr);
-	idx->len = QSE_AWK_VAL_MAP_ITR_KEY_LEN(iptr);
+	idx->set (QSE_AWK_VAL_MAP_ITR_KEY(iptr));
 
 	return itr;
 }
diff --git a/qse/lib/awk/run.c b/qse/lib/awk/run.c
index 1662f0eb..d2722878 100644
--- a/qse/lib/awk/run.c
+++ b/qse/lib/awk/run.c
@@ -1,5 +1,5 @@
 /*
- * $Id: run.c 469 2011-05-21 16:16:18Z hyunghwan.chung $
+ * $Id: run.c 477 2011-05-24 04:22:40Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -260,9 +260,9 @@ typedef qse_awk_val_t* (*binop_func_t) (
 typedef qse_awk_val_t* (*eval_expr_t) (qse_awk_rtx_t* run, qse_awk_nde_t* nde);
 
 #ifdef NDEBUG
-#define xstr_to_cstr(x) ((qse_cstr_t*)x)
+#	define xstr_to_cstr(xstr) ((qse_cstr_t*)xstr)
 #else
-static qse_cstr_t* xstr_to_cstr (qse_xstr_t* xstr)
+static QSE_INLINE qse_cstr_t* xstr_to_cstr (qse_xstr_t* xstr)
 {
 	/* i use this function to typecast qse_cstr_t* to 
 	 * qse_xstr_t* instead of direct typecasting.