diff --git a/lib/comp.c b/lib/comp.c
index e738364..18da41e 100644
--- a/lib/comp.c
+++ b/lib/comp.c
@@ -473,7 +473,8 @@ static int check_block_expression_as_body (hcl_t* hcl, hcl_cnode_t* c, const hcl
 	{
 	no_block:
 		hcl_setsynerrbfmt (
-			hcl, HCL_SYNERR_BLOCK, (car? HCL_CNODE_GET_LOC(car): c? HCL_CNODE_GET_LOC(c): HCL_CNODE_GET_LOC(ctx)), HCL_NULL,
+			hcl, HCL_SYNERR_BLOCK,
+			(car? HCL_CNODE_GET_LOC(car): c? HCL_CNODE_GET_LOC(c): HCL_CNODE_GET_LOC(ctx)), HCL_NULL,
 			"block expression expected as '%.*js' body", HCL_CNODE_GET_TOKLEN(ctx), HCL_CNODE_GET_TOKPTR(ctx)
 		);
 		return -1;
@@ -534,7 +535,8 @@ static int check_block_expression_as_body (hcl_t* hcl, hcl_cnode_t* c, const hcl
 
 		hcl_setsynerrbfmt (
 			hcl, HCL_SYNERR_BANNED, HCL_CNODE_GET_LOC(cdr), HCL_NULL,
-			"redundant expression prohibited after '%.*js' body", HCL_CNODE_GET_TOKLEN(ctx), HCL_CNODE_GET_TOKPTR(ctx)
+			"redundant expression prohibited after '%.*js' body",
+			HCL_CNODE_GET_TOKLEN(ctx), HCL_CNODE_GET_TOKPTR(ctx)
 		);
 		return -1;
 	}
@@ -2639,7 +2641,8 @@ static int compile_class (hcl_t* hcl, hcl_cnode_t* src, int defclass)
 	}
 	else
 	{
-		if (emit_byte_instruction(hcl, HCL_CODE_PUSH_NIL,HCL_CNODE_GET_LOC(cmd)) <= -1) return -1; /* push nil for class name of an anonymous class */
+		/* push nil for class name of an anonymous class */
+		if (emit_byte_instruction(hcl, HCL_CODE_PUSH_NIL, HCL_CNODE_GET_LOC(cmd)) <= -1) return -1;
 	}
 	POP_CFRAME (hcl);
 
@@ -2814,35 +2817,109 @@ static HCL_INLINE int compile_class_p2 (hcl_t* hcl)
 
 /* ========================================================================= */
 
+static int check_fun_attr_list (hcl_t* hcl, hcl_cnode_t* attr_list, unsigned int* fun_type)
+{
+	unsigned int ft;
+
+	ft = 0;
+
+	HCL_ASSERT (hcl, attr_list != HCL_NULL);
+	HCL_ASSERT (hcl, HCL_CNODE_IS_CONS_CONCODED(attr_list, HCL_CONCODE_XLIST) ||
+	                 HCL_CNODE_IS_ELIST_CONCODED(attr_list, HCL_CONCODE_XLIST));
+
+	if (HCL_CNODE_IS_CONS(attr_list))
+	{
+		hcl_cnode_t* c, * a;
+		const hcl_ooch_t* tokptr;
+		hcl_oow_t toklen;
+
+		c = attr_list;
+		while (c)
+		{
+			a = HCL_CNODE_CONS_CAR(c);
+
+			tokptr = HCL_CNODE_GET_TOKPTR(a);
+			toklen = HCL_CNODE_GET_TOKLEN(a);
+
+			if (!HCL_CNODE_IS_TYPED(a, HCL_CNODE_SYMLIT))
+			{
+				hcl_setsynerrbfmt (
+					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(a), HCL_NULL,
+					"invalid function attribute name '%.*js'", toklen, tokptr);
+				return -1;
+			}
+
+			if (hcl_comp_oochars_bcstr(tokptr, toklen, "class") == 0 ||
+			    hcl_comp_oochars_bcstr(tokptr, toklen, "c") == 0)
+			{
+				if (ft != 0)
+				{
+				conflicting:
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(a), HCL_NULL,
+						"conflicting function attribute name '%.*js'", toklen, tokptr);
+					return -1;
+				}
+				ft = FUN_CM;
+			}
+			else if (hcl_comp_oochars_bcstr(tokptr, toklen, "classinst") == 0 ||
+			         hcl_comp_oochars_bcstr(tokptr, toklen, "ci") == 0)
+			{
+				if (ft != 0) goto conflicting;
+				ft = FUN_CIM;
+			}
+			else
+			{
+				hcl_setsynerrbfmt (
+					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(a), HCL_NULL,
+					"unrecognized function attribute name '%.*js'", toklen, tokptr);
+				return -1;
+			}
+
+			c = HCL_CNODE_CONS_CDR(c);
+		}
+	}
+
+	*fun_type = ft;
+	return 0;
+}
+
 static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 {
-	hcl_cnode_t* cmd, * obj, * args;
+	hcl_cnode_t* cmd, * next;
 	hcl_oow_t va, nargs, nrvars, nlvars;
 	hcl_ooi_t jump_inst_pos, lfbase_pos, lfsize_pos;
 	hcl_oow_t saved_tv_wcount, tv_dup_start;
 	hcl_cnode_t* fun_name;
 	hcl_cnode_t* class_name;
+	hcl_cnode_t* arg_list;
+	hcl_cnode_t* fun_body;
 	hcl_cframe_t* cf;
-	unsigned int fun_type = FUN_PLAIN;
-	int named = 0;
+	unsigned int fun_type;
 
 	HCL_ASSERT (hcl, HCL_CNODE_IS_CONS(src));
 
 	saved_tv_wcount = hcl->c->tv.wcount;
 	cmd = HCL_CNODE_CONS_CAR(src);
-	obj = HCL_CNODE_CONS_CDR(src);
+	next = HCL_CNODE_CONS_CDR(src);
+	fun_name = HCL_NULL;
 	class_name = HCL_NULL;
+	arg_list = HCL_NULL;
+	fun_body = HCL_NULL;
+	fun_type = FUN_PLAIN;
 
 	HCL_ASSERT (hcl, HCL_CNODE_IS_SYMBOL_SYNCODED(cmd, HCL_SYNCODE_FUN) ||
 	                 HCL_CNODE_IS_TYPED(cmd, HCL_CNODE_FUN));
 
-	if (obj)
+	if (next)
 	{
-		hcl_cnode_t* tmp, * next;
+		hcl_cnode_t* tmp;
+		hcl_cnode_t* attr_list;
 
 		/* the reader ensures that the cdr field of a cons cell points to the next cell.
 		 * and only the field of the last cons cell is NULL. */
-		HCL_ASSERT (hcl, HCL_CNODE_IS_CONS(obj));
+		HCL_ASSERT (hcl, HCL_CNODE_IS_CONS(next));
+		attr_list = HCL_NULL;
 
 		/* fun (arg..)
 		 * fun name (arg..)
@@ -2850,12 +2927,12 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 		 * fun(#attr..) (arg..)
 		 * fun(#attr..) class:name(arg..)
 		 */
-		next = obj;
+
 		tmp = HCL_CNODE_CONS_CAR(next);
 		if (HCL_CNODE_IS_SYMBOL_PLAIN(tmp))
 		{
 			/* 'fun' followed by name */
-		got_name:
+		fun_got_name:
 			/* name must be followed by argument list */
 			fun_name = tmp;
 
@@ -2863,10 +2940,10 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 			if (!next)
 			{
 				hcl_setsynerrbfmt (
-					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
-					"'%.*js' name '%.*js' not followed by ( or :",
-					HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd),
-					HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name));
+					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(fun_name), HCL_NULL,
+					"function name '%.*js' not followed by ( or : for '%.*js'",
+					HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name),
+					HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 				return -1;
 			}
 
@@ -2881,10 +2958,10 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 				if (!next)
 				{
 					hcl_setsynerrbfmt (
-						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
-						"no '%.*js' name after class name '%.*js' and :",
-						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd),
-						HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name));
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(class_name), HCL_NULL,
+						"no function name after class name '%.*js:' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 
@@ -2892,54 +2969,187 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 				if (!HCL_CNODE_IS_SYMBOL_PLAIN(tmp))
 				{
 					hcl_setsynerrbfmt (
-						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
-						"invalid '%.*js' name '%.*js' after class name and :",
-						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd),
-						HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp));
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(tmp), HCL_NULL,
+						"invalid function name '%.*js' after '%.*js:' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp),
+						HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 				fun_name = tmp;
+				fun_type = FUN_IM;
+				if (attr_list && check_fun_attr_list(hcl, attr_list, &fun_type) <= -1) return -1;
+				fun_type |= 0x100; /* indicate that the function was defined in 'fun class:name()' style */
+
+				next = HCL_CNODE_CONS_CDR(next);
+				if (!next)
+				{
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(fun_name), HCL_NULL,
+						"function name '%.*js:%.*js' not followed by ( for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name),
+						HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					return -1;
+				}
+
+				tmp = HCL_CNODE_CONS_CAR(next); /* pointing to argument list */
+
+				if (is_in_class_init_scope(hcl))
+				{
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(fun_name), HCL_NULL,
+						"class name '%.*js' before :'%.*js' prohibited in class initialization context",
+						HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name),
+						HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name));
+					return -1;
+				}
+			}
+			else
+			{
+				/* no 'class:' part after 'fun' */
+				if (is_in_class_init_scope(hcl))
+				{
+					/* TODO:THIS IS ALSO WRONG.
+					 *  class X {
+					 *    a := (fun x(){}) ## this context is also class_init_scope. so the check above isn't good enough
+					 *  } */
+					fun_type = FUN_IM;
+					if (attr_list && check_fun_attr_list(hcl, attr_list, &fun_type) <= -1) return -1;
+				}
+				else
+				{
+					/* as of now, the plain function doesn't support attribute list.
+					 * this can change in the future. */
+					if (attr_list)
+					{
+						hcl_setsynerrbfmt (
+							hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(attr_list), HCL_NULL,
+							"unsupported attribute list for plain function '%.*js'",
+							HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name));
+						return -1;
+					}
+				}
 			}
 		}
-		else if (HCL_CNODE_IS_CONS(tmp))
+
+		if (HCL_CNODE_IS_CONS_CONCODED(tmp, HCL_CONCODE_XLIST) ||
+		    HCL_CNODE_IS_ELIST_CONCODED(tmp, HCL_CONCODE_XLIST))
 		{
 			/* 'fun' followed by attribute or argument list */
-			next = HCL_CNODE_CONS_CDR(next);
-			if (!next)
+			arg_list = tmp;
+			if (fun_name)
 			{
+				/* argument list for sure
+				 *   fun class:name()
+				 *   fun name      ()
+				 *                 ^  */
+				next = HCL_CNODE_CONS_CDR(next); /* point past argument list */
+				if (!next)
+				{
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
+						"no function body after argument list of function '%.*js' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					return -1;
+				}
+				fun_body = next;
+			}
+			else
+			{
+				/* not clear if it is attribute list or argument list */
+				next = HCL_CNODE_CONS_CDR(next); /* point past attribute/argument list */
+				if (!next)
+				{
+					/* TODO: guess if the current list looks like attribute list or
+					 *       not by inspecting elements and produce better error mesage.
+					 *       another hack is to disallow ELIST as attribute list? */
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
+						"unamed function not followed by function body for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					return -1;
+				}
+
+				tmp = HCL_CNODE_CONS_CAR(next);
+				if (HCL_CNODE_IS_SYMBOL_PLAIN(tmp))
+				{
+					/* it is attribute list for sure. fun(#attr..) name */
+					attr_list = arg_list;
+					arg_list = HCL_NULL;
+					goto fun_got_name;
+				}
+				else if (HCL_CNODE_IS_CONS_CONCODED(tmp, HCL_CONCODE_XLIST) ||
+				         HCL_CNODE_IS_ELIST_CONCODED(tmp, HCL_CONCODE_XLIST))
+				{
+					/* fun(#attr..) (arg..) .. */
+					attr_list = arg_list;
+					arg_list = tmp;
+
+					next = HCL_CNODE_CONS_CDR(next); /* point past argument list */
+					if (!next)
+					{
+						hcl_setsynerrbfmt (
+							hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
+							"no function body after attribute list and argument list of unamed function for '%.*js'",
+							HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+						return -1;
+					}
+					fun_body = next;
+				}
+				else
+				{
+					/* fun(arg..) .. */
+					fun_body = next;
+				}
+			}
+
+			if (!fun_name && is_in_class_init_scope(hcl))
+			{
+				/* TODO: it must allow as rvalue..
+				 * class X {
+				 *     b := (fun() {}) ## this is allowed  <- TODO: not supported yet
+				 *     fun() {} ## this is prohibited
+				 * }
+				 */
 				hcl_setsynerrbfmt (
 					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
-					"'%.*js' not defined with body",
-					HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd),
-					HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp));
+					"unnamed function defined with '%.*js' prohibited in class initialziation context",
+					HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 				return -1;
 			}
-
-			tmp = HCL_CNODE_CONS_CAR(next);
-			if (HCL_CNODE_IS_SYMBOL_PLAIN(tmp))
-			{
-				/* fun(#attr..) name */
-				goto got_name;
-			}
-			else if (HCL_CNODE_IS_CONS(tmp))
-			{
-				/* fun(#attr..) (arg..)  */
-			}
-
-			/* fall down to handle the function body */
 		}
 		else
 		{
-			hcl_setsynerrbfmt (
-				hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
-				"'%.*js' not followed by name or (, but followed by '%.*js'",
-				HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd),
-				HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp));
+			/* not valid argument list or attribute list
+			 * fun if         ## cmd is 'fun', fun_name is nil
+			 * fun a if       ## cmd is 'fun', fun_name is 'a'
+			 * fun a:b if     ## cmd is 'fun', fun_name is 'b'
+			 * fun self.a     ## cmd is 'fun', fun_name is nil
+			 */
+			if (fun_name)
+			{
+				hcl_setsynerrbfmt (
+					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(tmp), HCL_NULL,
+					"'%.*js' not followed by ( but followed by '%.*js'",
+					HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name),
+					HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp));
+			}
+			else
+			{
+				hcl_setsynerrbfmt (
+					hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(tmp), HCL_NULL,
+					"invalid function name '%.*js' for '%.*js'",
+					HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp),
+					HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+			}
 			return -1;
 		}
 	}
 	else
 	{
+		/* nothing after 'fun' (e.g. fun ) */
 		hcl_setsynerrbfmt (
 			hcl, HCL_SYNERR_FUN, HCL_CNODE_GET_LOC(cmd), HCL_NULL,
 			"'%.*js' not followed by name or (",
@@ -2947,180 +3157,17 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 		return -1;
 	}
 
-	if (obj && HCL_CNODE_IS_CONS(obj))
-	{
-		/* inaccurate pre-check if 'fun' is followed by an argument list
-		 * without a function name. */
-		args = HCL_CNODE_CONS_CAR(obj);
-		if (!HCL_CNODE_IS_ELIST_CONCODED(args, HCL_CONCODE_XLIST) &&
-		    !HCL_CNODE_IS_CONS_CONCODED(args, HCL_CONCODE_XLIST))
-		{
-			/* not followed by an argument list */
-			named = 1;
-			goto named_function;
-		}
-	}
-
-	if (named)
-	{
-	named_function:
-		if (!obj)
-		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAMELIST, HCL_CNODE_GET_LOC(src), HCL_NULL, "no name in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-			return -1;
-		}
-		else if (!HCL_CNODE_IS_CONS(obj))
-		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_DOTBANNED, HCL_CNODE_GET_LOC(obj), HCL_CNODE_GET_TOK(obj), "redundant cdr in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-			return -1;
-		}
-
-		fun_name = HCL_CNODE_CONS_CAR(obj);
-		if (is_in_class_init_scope(hcl))
-		{
-			if ((HCL_CNODE_IS_DBLCOLONS(fun_name) || HCL_CNODE_IS_COLONSTAR(fun_name)))
-			{
-				/* class method - (fun ::xxxx () ...) inside class definition */
-				/* class instantiation method - (fun :*xxxx() ...) inside class definition */
-				obj = HCL_CNODE_CONS_CDR(obj);
-				if (!obj)
-				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAMELIST, HCL_CNODE_GET_LOC(src), HCL_NULL, "no name in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-					return -1;
-				}
-
-				fun_type = HCL_CNODE_IS_DBLCOLONS(fun_name)? FUN_CM: FUN_CIM;
-				fun_name = HCL_CNODE_CONS_CAR(obj); /* advance to the actual name */
-			}
-			else
-			{
-				if (HCL_CNODE_IS_SYMBOL_PLAIN(fun_name))
-				{
-					/* probably this form - fun XXX:yyy () ...
-					 * the class name must not be specified in the class initialization scope */
-					hcl_cnode_t* tmp;
-					tmp = HCL_CNODE_CONS_CDR(obj);
-					if (tmp && HCL_CNODE_IS_CONS(tmp))
-					{
-						tmp = HCL_CNODE_CONS_CAR(tmp);
-						if (HCL_CNODE_IS_COLON(tmp) || HCL_CNODE_IS_DBLCOLONS(tmp) || HCL_CNODE_IS_COLONSTAR(tmp)/*(HCL_CNODE_IS_SYMBOL_PLAIN(tmp)*/)
-						{
-							hcl_setsynerrbfmt (
-								hcl, HCL_SYNERR_VARNAME,
-								HCL_CNODE_GET_LOC(fun_name), HCL_CNODE_GET_TOK(fun_name),
-								"function name not valid followed by %.*js",
-								HCL_CNODE_GET_TOKLEN(tmp), HCL_CNODE_GET_TOKPTR(tmp));
-							return -1;
-						}
-					}
-				}
-
-				fun_type = FUN_IM;
-			}
-		}
-		else if (HCL_CNODE_IS_SYMBOL_PLAIN(fun_name))
-		{
-			hcl_cnode_t* tmp, marker;
-			tmp = HCL_CNODE_CONS_CDR(obj);
-			if (tmp && HCL_CNODE_IS_CONS(tmp))
-			{
-				hcl_cnode_t* marker;
-				marker = HCL_CNODE_CONS_CAR(tmp);
-				if (HCL_CNODE_IS_COLON(marker) || HCL_CNODE_IS_DBLCOLONS(marker) || HCL_CNODE_IS_COLONSTAR(marker))
-				{
-					/* fun A:aaa A::aaa A:*aaa */
-
-					tmp = HCL_CNODE_CONS_CDR(tmp);
-					if (tmp && HCL_CNODE_IS_CONS(tmp))
-					{
-						hcl_cnode_t* cand;
-						cand = HCL_CNODE_CONS_CAR(tmp);
-						if (HCL_CNODE_IS_SYMBOL_PLAIN(cand))
-						{
-							/* out-of-class method definition
-							 * for fun String:length() { ...  },
-							 * class_name is String, fun_name is length. */
-							fun_type = HCL_CNODE_IS_DBLCOLONS(marker)? FUN_CM:
-							           HCL_CNODE_IS_COLONSTAR(marker)? FUN_CIM: FUN_IM;
-
-							/* indicates that this method is defined using the AAA:bbb syntax.
-							 * the form of method defintion can still be inside a class if this
-							 * form is place inside another normal method.
-							 *  class X {
-							 *    fun x()  {
-							 *      fun J:q() { .... } ## this defintion
-							 *    }
-							 *  }
-							 * */
-							fun_type |= 0x100;
-
-							class_name = fun_name;
-							fun_name = HCL_CNODE_CONS_CAR(tmp);
-							obj = tmp;
-						}
-					}
-				}
-			}
-		}
-
-		if (!HCL_CNODE_IS_SYMBOL(fun_name))
-		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME,
-				HCL_CNODE_GET_LOC(fun_name), HCL_NULL,
-				"invalid function name '%.*js' for '%.*js'",
-				HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name),
-				HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-			return -1;
-		}
-
-		if (HCL_CNODE_SYMBOL_SYNCODE(fun_name)) /*|| HCL_OBJ_GET_FLAGS_KERNEL(fun_name) >= 1) */
-		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME,
-				HCL_CNODE_GET_LOC(fun_name), HCL_NULL,
-				"special symbol '%.*js' not to be used as function name",
-				HCL_CNODE_GET_TOKLEN(fun_name), HCL_CNODE_GET_TOKPTR(fun_name));
-			return -1;
-		}
-
-		obj = HCL_CNODE_CONS_CDR(obj);
-	}
-	else
-	{
-		HCL_ASSERT (hcl, HCL_CNODE_IS_SYMBOL_SYNCODED(cmd, HCL_SYNCODE_FUN) ||
-		                 HCL_CNODE_IS_TYPED(cmd, HCL_CNODE_FUN));
-		fun_name = HCL_NULL;
-	}
-
-	if (!obj)
-	{
-	no_arg_list:
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAMELIST, HCL_CNODE_GET_LOC(src), HCL_NULL,
-			"argument list missing in %.*js",
-			HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-		return -1;
-	}
-	else if (!HCL_CNODE_IS_CONS(obj))
-	{
-	redundant_cdr:
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_DOTBANNED, HCL_CNODE_GET_LOC(obj), HCL_CNODE_GET_TOK(obj), "redundant cdr in argument list in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-		return -1;
-	}
-
 	/* process the argument list */
 	va = 0;
 	nargs = 0;
 	nrvars = 0;
-	args = HCL_CNODE_CONS_CAR(obj);
-	HCL_ASSERT (hcl, args != HCL_NULL);
 
-	if (HCL_CNODE_IS_ELIST_CONCODED(args, HCL_CONCODE_XLIST))
+	HCL_ASSERT (hcl, HCL_CNODE_IS_ELIST_CONCODED(arg_list, HCL_CONCODE_XLIST) ||
+	                 HCL_CNODE_IS_CONS_CONCODED(arg_list, HCL_CONCODE_XLIST));
+	if (HCL_CNODE_IS_ELIST_CONCODED(arg_list, HCL_CONCODE_XLIST))
 	{
-		/* empty list - no argument - (fun () (+ 10 20)) */
-	}
-	else if (!HCL_CNODE_IS_CONS_CONCODED(args, HCL_CONCODE_XLIST))
-	{
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAMELIST, HCL_CNODE_GET_LOC(args), HCL_CNODE_GET_TOK(args), "no argument list in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
-		return -1;
+		/* empty list - no argument - fun () {+ 10 20} */
+		/* do nothing */
 	}
 	else
 	{
@@ -3128,22 +3175,33 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 		int in_ret_args = 0;
 
 		tv_dup_start = hcl->c->tv.s.len;
-		dcl = args;
+		dcl = arg_list;
 		do
 		{
 			arg = HCL_CNODE_CONS_CAR(dcl);
 
 			if (in_ret_args)
 			{
-				if (!HCL_CNODE_IS_SYMBOL(arg))
+				if (!HCL_CNODE_IS_SYMBOL_PLAIN_IDENT(arg))
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "return variable not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					/* in 'fun x (x :: 20) { }', '20' is not a valid return variable name.
+					 * in 'fun x (x :: if) { }', 'if' is not a valid return variable name. */
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+						"invalid return variable '%.*js' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 
+				/* TODO: delete this error check once SYNCODE stuffs are all deleted */
 				if (HCL_CNODE_IS_SYMBOL(arg) && HCL_CNODE_SYMBOL_SYNCODE(arg) /* || HCL_OBJ_GET_FLAGS_KERNEL(arg) >= 2 */)
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "special symbol not to be declared as return variable in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+						"special symbol '%.*js' used as return variable for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 
@@ -3151,7 +3209,12 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 				{
 					if (hcl->errnum == HCL_EEXIST)
 					{
-						hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAMEDUP, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "return variable duplicate in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+						/* in 'fun x (y :: z z) {}', the second 'z' is duplicate */
+						hcl_setsynerrbfmt (
+							hcl, HCL_SYNERR_VARNAMEDUP, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+							"duplicate return variable '%.*js' for '%.*js'",
+							HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+							HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					}
 					return -1;
 				}
@@ -3165,7 +3228,13 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 				}
 				else
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_CNODE, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "unexpected element in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					/* in 'fun x (... a) {}', 'a' is an unexpected token.
+					 * only ')' or '::' can follow ... */
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_CNODE, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+						"unexpected token '%.*js' after '...' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 			}
@@ -3179,16 +3248,25 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 				{
 					va = 1;
 				}
-				else if (!HCL_CNODE_IS_SYMBOL(arg))
+				else if (!HCL_CNODE_IS_SYMBOL_PLAIN_IDENT(arg))
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "argument not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					hcl_setsynerrbfmt (
+						hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+						"invalid argument name '%.*js' for '%.*js'",
+						HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+						HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 				else
 				{
+					/* TODO: delete this error check once SYNCODE stuffs are all deleted */
 					if (HCL_CNODE_IS_SYMBOL(arg) && HCL_CNODE_SYMBOL_SYNCODE(arg) /* || HCL_OBJ_GET_FLAGS_KERNEL(arg) >= 2 */)
 					{
-						hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDARGNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "special symbol not to be declared as argument in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+						hcl_setsynerrbfmt (
+							hcl, HCL_SYNERR_BANNEDARGNAME, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+							"special symbol '%.*js' used as argument name for '%.*js'",
+							HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+							HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 						return -1;
 					}
 
@@ -3196,7 +3274,11 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 					{
 						if (hcl->errnum == HCL_EEXIST)
 						{
-							hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAMEDUP, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "argument duplicate in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+							hcl_setsynerrbfmt (
+								hcl, HCL_SYNERR_ARGNAMEDUP, HCL_CNODE_GET_LOC(arg), HCL_NULL,
+								"duplicate argument name '%.*js' for '%.*js'",
+								HCL_CNODE_GET_TOKLEN(arg), HCL_CNODE_GET_TOKPTR(arg),
+								HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 						}
 						return -1;
 					}
@@ -3209,7 +3291,8 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 
 			if (!HCL_CNODE_IS_CONS(dcl))
 			{
-				hcl_setsynerrbfmt (hcl, HCL_SYNERR_DOTBANNED, HCL_CNODE_GET_LOC(dcl), HCL_CNODE_GET_TOK(dcl), "redundant cdr in argument list in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+				hcl_setsynerrbfmt (hcl, HCL_SYNERR_DOTBANNED, HCL_CNODE_GET_LOC(dcl), HCL_CNODE_GET_TOK(dcl),
+					"redundant cdr in argument list in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 				return -1;
 			}
 		}
@@ -3222,18 +3305,23 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 		 * block arguments, evaluation which is done by message passing
 		 * limits the number of arguments that can be passed. so the
 		 * check is implemented */
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGFLOOD, HCL_CNODE_GET_LOC(args), HCL_NULL, "too many(%zu) arguments in %.*js", nargs, HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+		hcl_setsynerrbfmt (
+			hcl, HCL_SYNERR_ARGFLOOD, HCL_CNODE_GET_LOC(arg_list), HCL_NULL,
+			"too many(%zu) arguments in %.*js", nargs,
+			HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 		return -1;
 	}
 
 	if (nrvars > MAX_CODE_NBLKLVARS)
 	{
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARFLOOD, HCL_CNODE_GET_LOC(args), HCL_NULL, "too many(%zu) return variables in %.*js", nrvars, HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+		hcl_setsynerrbfmt (
+			hcl, HCL_SYNERR_VARFLOOD, HCL_CNODE_GET_LOC(arg_list), HCL_NULL,
+			"too many(%zu) return variables in %.*js", nrvars,
+			HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 		return -1;
 	}
 	HCL_ASSERT (hcl, nargs + nrvars == hcl->c->tv.wcount - saved_tv_wcount);
 
-
 	/*
 	 * fun aa(a b) { ...	};
 	 * (fun aa(a b) { ... })
@@ -3242,10 +3330,9 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 	 * the variable declaration can't be placed before the block expression.
 	 * it is supported inside the block expression itself.
 	 */
-	hcl_cnode_t* blk;
-	blk = HCL_CNODE_CONS_CDR(obj);
-	if (check_block_expression_as_body(hcl, blk, cmd, FOR_NONE) <= -1) return -1;
-	obj = blk;
+	if (check_block_expression_as_body(hcl, fun_body, cmd, FOR_NONE) <= -1) return -1;
+
+	HCL_ASSERT (hcl, fun_body != HCL_NULL);
 	nlvars = 0; /* no known local variables until the actual block is processed */
 
 	HCL_ASSERT (hcl, nargs + nrvars + nlvars == hcl->c->tv.wcount - saved_tv_wcount);
@@ -3273,7 +3360,7 @@ static int compile_fun (hcl_t* hcl, hcl_cnode_t* src)
 	 * produce the long jump instruction (HCL_CODE_JUMP_FORWARD_X) */
 	if (emit_single_param_instruction(hcl, HCL_CODE_JUMP_FORWARD_0, MAX_CODE_JUMP, HCL_CNODE_GET_LOC(cmd)) <= -1) return -1;
 
-	SWITCH_TOP_CFRAME (hcl, COP_COMPILE_OBJECT_LIST, obj); /* 1 */
+	SWITCH_TOP_CFRAME (hcl, COP_COMPILE_OBJECT_LIST, fun_body); /* 1 */
 	PUSH_SUBCFRAME (hcl, COP_POST_FUN, fun_name); /* 3*/
 	cf = GET_SUBCFRAME(hcl);
 	cf->u.fun.fun_type = fun_type;
@@ -4640,7 +4727,7 @@ static HCL_INLINE int compile_dsymbol (hcl_t* hcl, hcl_cnode_t* obj)
 				/* if defined using A::xxx syntax, it's not possible to know the instance position of an instance variable.
 				 * class X [ a b ] {
 				 *   fun a() {
-				 *      fun J::t() {
+				 *      fun J:t() {
 				 *        ## J has nothing to to with X in priciple even if J may point to X when a() is executed.
 				 *        ## it's not meaningful to look up the variable `a` in the context of class X.
 				 *        ## it must be prohibited to access instance variables using the self or super prefix
@@ -4659,7 +4746,7 @@ static HCL_INLINE int compile_dsymbol (hcl_t* hcl, hcl_cnode_t* obj)
 		}
 		else if (hcl_comp_oochars_bcstr(name.ptr, sep - (const hcl_ooch_t*)name.ptr, "super") == 0)
 		{
-			if (fbi->fun_type >> 8) /* if defined using A::xxx syntax */
+			if (fbi->fun_type >> 8) /* if defined using A:xxx syntax */
 			{
 				hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(obj), HCL_CNODE_GET_TOK(obj), "not allowed to prefix with super in out-of-class method context");
 				return -1;
@@ -6107,7 +6194,10 @@ static HCL_INLINE int post_fun (hcl_t* hcl)
 			{
 				/* something wrong - this must not happen because the reader must prevent this
 				 * but if it happens, it is a syntax error */
-				hcl_setsynerrbfmt(hcl, HCL_SYNERR_BANNED, HCL_CNODE_GET_LOC(class_name), HCL_CNODE_GET_TOK(class_name), "class name prohibited");
+				hcl_setsynerrbfmt (
+					hcl, HCL_SYNERR_BANNED, HCL_CNODE_GET_LOC(class_name), HCL_NULL,
+					"class name '%.js' prohibited class initialization context",
+					HCL_CNODE_GET_TOKLEN(class_name), HCL_CNODE_GET_TOKPTR(class_name));
 				return -1;
 			}
 
diff --git a/lib/hcl-prv.h b/lib/hcl-prv.h
index 837c531..b83a2a6 100644
--- a/lib/hcl-prv.h
+++ b/lib/hcl-prv.h
@@ -400,6 +400,16 @@ enum hcl_cnode_type_t
 	HCL_CNODE_SELF,
 	HCL_CNODE_SUPER,
 
+	HCL_CNODE_CONS,
+	HCL_CNODE_ELIST, /* empty list */
+	HCL_CNODE_SHELL, /* pseudo-node to hold another actual node */
+
+	/* If HCL_CNODE_SHELL is not the last item before the horizontal line,
+	 * HCL_CNDOE_IS_FOR_DATA(x) must be revised */
+	/* ------------------------------------------------------------------ */
+
+	/* the cnode types from here don't represent actual data.
+	 * these represent syntactical elements of the language only.  */
 	HCL_CNODE_CLASS,
 	HCL_CNODE_FUN,
 	HCL_CNODE_DO,
@@ -423,10 +433,6 @@ enum hcl_cnode_type_t
 	HCL_CNODE_COLONGT, /* :> */
 	HCL_CNODE_COLONLT, /* :< */
 	HCL_CNODE_COLONSTAR, /* :* */
-
-	HCL_CNODE_CONS,
-	HCL_CNODE_ELIST, /* empty list */
-	HCL_CNODE_SHELL  /* pseudo-node to hold another actual node */
 };
 typedef enum hcl_cnode_type_t hcl_cnode_type_t;
 
@@ -444,6 +450,7 @@ typedef enum hcl_cnode_flag_t hcl_cnode_flag_t;
 #define HCL_CNODE_GET_TOKLEN(x) ((x)->cn_tok.len)
 
 #define HCL_CNODE_IS_TYPED(x, _type) ((x)->cn_type == _type)
+#define HCL_CNODE_IS_FOR_DATA(x) ((x)->cn_type <= HCL_CNODE_SHELL)
 
 #define HCL_CNODE_IS_ELLIPSIS(x) ((x)->cn_type == HCL_CNODE_ELLIPSIS)
 #define HCL_CNODE_IS_TRPCOLONS(x) ((x)->cn_type == HCL_CNODE_TRPCOLONS)
diff --git a/lib/read.c b/lib/read.c
index ca92566..8bbb2aa 100644
--- a/lib/read.c
+++ b/lib/read.c
@@ -896,7 +896,27 @@ static HCL_INLINE int can_colon_list (hcl_t* hcl)
 		if (HCL_CNODE_IS_SYMBOL_SYNCODED(HCL_CNODE_CONS_CAR(rstl->head), HCL_SYNCODE_FUN) ||
 		    HCL_CNODE_IS_TYPED(HCL_CNODE_CONS_CAR(rstl->head), HCL_CNODE_FUN))
 		{
-			if (rstl->count == 2) return 2;
+			hcl_cnode_t* tmp, * next;
+			next = HCL_CNODE_CONS_CDR(rstl->head);
+			HCL_ASSERT (hcl, next != HCL_NULL);
+			tmp = HCL_CNODE_CONS_CAR(next); /* second item */
+			if (rstl->count == 2)
+			{
+				/* fun class:name() *... */
+				if (HCL_CNODE_IS_SYMBOL_PLAIN(tmp)) return 2;
+			}
+			else if (rstl->count == 3)
+			{
+				/* fun(#c) class:name() ... */
+				if (HCL_CNODE_IS_CONS_CONCODED(tmp, HCL_CONCODE_XLIST) ||
+				    HCL_CNODE_IS_ELIST_CONCODED(tmp, HCL_CONCODE_XLIST))
+				{
+					next = HCL_CNODE_CONS_CDR(next);
+					HCL_ASSERT (hcl, next != HCL_NULL);
+					tmp = HCL_CNODE_CONS_CAR(next); /* third item */
+					if (HCL_CNODE_IS_SYMBOL_PLAIN(tmp)) return 2;
+				}
+			}
 		}
 
 		return 0; /* the first key is not colon-delimited. so not allowed to colon-delimit other keys  */
@@ -908,11 +928,17 @@ static HCL_INLINE int can_colon_list (hcl_t* hcl)
 	cc = (hcl_concode_t)LIST_FLAG_GET_CONCODE(rstl->flagv);
 	if (cc == HCL_CONCODE_XLIST)
 	{
+		hcl_cnode_t* tmp;
+
 		/* method defintion with fun  - e.g. fun String:length()
 		 * ugly that this reader must know about the meaning of fun */
 		if (rstl->count > 1) return 0;
+
 		/* ugly dual use of a colon sign. switch to MLIST if the first element
 		 * is delimited by a colon. e.g. (obj:new 10 20 30)  */
+		tmp = HCL_CNODE_CONS_CAR(rstl->head);
+		if (!HCL_CNODE_IS_FOR_DATA(tmp)) return 0;
+
 		LIST_FLAG_SET_CONCODE(rstl->flagv, HCL_CONCODE_MLIST);
 		rstl->flagv &= ~JSON;
 	}
diff --git a/t/class-5001.err b/t/class-5001.err
index e17ff9e..4fc314a 100644
--- a/t/class-5001.err
+++ b/t/class-5001.err
@@ -18,11 +18,11 @@ class B + ##ERROR: syntax error - prohibited binary selector '+'
 J := 11
 class B {
 	if (== J 10) {
-		fun :*newA() {
+		fun(#ci) newA() {
 			return self
 		}
 	} else {
-		fun :*newB() {
+		fun(#ci) newB() {
 			return self
 		}
 	}
@@ -45,7 +45,7 @@ class B [ x y ] {
 };
 
 class X :: B [ a b ] {
-	fun :* new(t) {
+	fun(#ci) new(t) {
 		| a |
 		set self.a t;
 		set a 100;
@@ -67,24 +67,25 @@ class X :: B [ a b ] {
 ---
 
 class X {
-	fun :* xxx() {
+	fun(#ci) xxx() {
 		return X;
 	}
-	fun :* qqq() {
+
+	fun(#ci) qqq() {
 		return "hello"
 	}
 
-	fun String:length()  { ##ERROR: syntax error - function name not valid
-		return (str.length self)
+	fun String:length()  { ##ERROR: syntax error - class name 'String' before :'length' prohibited in class initialization context
+		return (core.basicSize self)
 	}
 }
 
 ---
 class X {
-	fun :* xxx() {
+	fun(#ci) xxx() {
 		return X;
 	}
-	fun :* qqq() {
+	fun(#ci) qqq() {
 		return "hello"
 	}
 }
@@ -109,7 +110,7 @@ fun X:xxx() { ##ERROR: exception not handled - "not class"
 ## and the clase instantiation method can't specify the size
 ## you can't place an item in the arrya at all.
 
-fun Array:*boom() {
+fun(#ci) Array:boom() {
 	core.basicAtPut self 0 10 ##ERROR: exception not handled - "position(0) out of range - negative or greater than or equal to 0"
 	printf "%O" self
 	return self
@@ -119,7 +120,7 @@ Array:boom
 ---
 
 class X [ a  b c ] {
-	fun :* new () {
+	fun(#ci) new () {
 		self.a := 20
 		return self
 	}
@@ -186,3 +187,10 @@ F := (class F { ##ERROR: exception not handle - "prohibited redefintion of F"
 ##F := 30
 ##class F { ##ERROR: exception not handled - "prohibited redefintion of F"
 ##}
+
+
+---
+class a {
+	fun() { ##ERROR: syntax error - unnamed function defined with 'fun' prohibited in class initialziation context
+	}
+}
diff --git a/t/feed-5001.err b/t/feed-5001.err
index 326698e..1685032 100644
--- a/t/feed-5001.err
+++ b/t/feed-5001.err
@@ -146,6 +146,11 @@ fun :* fun1() { ##ERROR: syntax error - invalid function name ':*' for 'fun'
 
 ---
 
+fun(#ci) fun1() { ##ERROR: syntax error - unsupported attribute list for plain function 'fun1'
+}
+
+---
+
 (10 + 20 30) ##ERROR: syntax error - redundant operand '30'
 
 ---
diff --git a/t/fun-01.hcl b/t/fun-01.hcl
index 9ca1aec..2c13af2 100644
--- a/t/fun-01.hcl
+++ b/t/fun-01.hcl
@@ -97,7 +97,7 @@ if (== y 29) {
 ## --------------------------------------
 
 defclass A [ a b c ] {
-	fun :* newInstance(x y z) {
+	fun(#ci) newInstance(x y z) {
 		set a x
 		set b y
 		set c z
@@ -113,8 +113,15 @@ k := (A:newInstance 11 22 33);
 ##set k (A:newInstance 11 22 33);
 
 set v (k:get-a);
-if (== v 11) {
-	printf "OK - %d\n" v;
-} else {
-	printf "ERROR - %d\n" v;
-};
+if (== v 11) { printf "OK - %d\n" v; } else { printf "ERROR - %d, ot 11\n" v; };
+
+## --------------------------------------
+
+k := (fun (x) { + x 20 }) ## (+ x 20) would be syntax error, must be { + x 20 }
+v := (k 10)
+if (== v 30) { printf "OK - %d\n" v } else { printf "ERROR - %d, not 30\n" v };
+
+## --------------------------------------
+fun k(x) (+ x 30)  ## (+ x 30) is valid function body
+v := (k 10)
+if (== v 40) { printf "OK - %d\n" v } else { printf "ERROR - %d, not 40\n" v };
diff --git a/t/insta-01.hcl b/t/insta-01.hcl
index 3a1c43f..b2be6f9 100644
--- a/t/insta-01.hcl
+++ b/t/insta-01.hcl
@@ -14,7 +14,7 @@ fun Number: ~= (oprnd) { return (~= self oprnd) }
 
 class A [ a b c ]  {
 
-	fun :*newInstance(x y z) {
+	fun(#ci) newInstance(x y z) {
 		set a x;
 		set b y;
 		set c z;
@@ -28,7 +28,7 @@ class A [ a b c ]  {
 
 class B :: A [ d e f ] {
 
-	fun :*newInstance(x y z) {
+	fun(#ci) newInstance(x y z) {
 		super:newInstance (* x 2) (* y 2) (* z 2);
 		set d x;
 		set e y;
@@ -36,9 +36,9 @@ class B :: A [ d e f ] {
 		return self;
 	};
 
-	fun :: getSuper() { return super; };
-	###fun :: getSuperclass() { return (self:superclass); };
-	fun :: getSelf() { return self; };
+	fun(#c) getSuper() { return super; };
+	###fun(#c) getSuperclass() { return (self:superclass); };
+	fun(#c) getSelf() { return self; };
 
 	fun sum() {
 		return (+ (super:get-a) (super:get-b) (super:get-c) self.d self.e self.f);
diff --git a/t/insta-02.hcl b/t/insta-02.hcl
index f547487..91e4d41 100644
--- a/t/insta-02.hcl
+++ b/t/insta-02.hcl
@@ -12,7 +12,7 @@ fun Number: ~= (oprnd) { return (~= self oprnd) }
 ## --------------------------------------------------------------
 set t (
 	class [ x ] {
-		fun :* make() { x := 1234; return self; };
+		fun(#ci) make() { x := 1234; return self; };
 		fun get-x() { return x };
 	}
 );
@@ -40,7 +40,7 @@ else { printf "OK:  value is %d\n" v };
 ## --------------------------------------------------------------
 
 class X0 [ a b c d ] {
-        fun :*new() {
+        fun(#ci) new() {
                 return self;
         }
 
@@ -67,7 +67,7 @@ else { printf "OK:  value is %d\n" v }
 ## --------------------------------------------------------------
 
 class X1 [ a  b c ] {
-	fun :* new () {
+	fun(#classinst) new () {
 		self.a := 20
 		return self
 	}
@@ -108,11 +108,11 @@ class F [ j t ] {
 }
 
 class X2 [ a b c ] {
-	fun :* new () {
+	fun(#classinst) new () {
 		| j |
 		self.a := 20
 		j := (self.a  * 2)
-		fun F::get_x() { return (j * j) }
+		fun(#class) F:get_x() { return (j * j) }
 		return self
 	}
 }
@@ -124,7 +124,7 @@ else { printf "OK: value is %d\n" v }
 
 ## --------------------------------------------------------------
 class X3 {
-	fun :* new (a b) {
+	fun(#ci) new (a b) {
 		fun X3:sum() { return (fun(j) { return (j + (a + b)) }) }
 		return self;
 	}
@@ -136,15 +136,15 @@ else { printf "OK: value is %d\n" v }
 
 ## --------------------------------------------------------------
 class X4 {
-	fun :: t() {
+	fun(#class) t() {
 		| X5 |
 		class X5 { ## this X5 isn't the local variable X4
-			fun :: t() {
+			fun(#class)  t() {
 				X6 := (class {
-					fun :: t() {
+					fun(#class) t() {
 						| X7 |
 						X7 := (class { ## this X4 is the local variable X4
-							fun :: t() { return 60 }
+							fun(#class) t() { return 60 }
 						})
 						return 40
 					}
diff --git a/t/retvar-01.hcl b/t/retvar-01.hcl
index 65c2fb8..9e9a4a1 100644
--- a/t/retvar-01.hcl
+++ b/t/retvar-01.hcl
@@ -36,12 +36,12 @@
 		set X1 999;
 		set X2 888;
 
-		fun :: get ( :: x y)  {
+		fun(#class) get ( :: x y)  {
 			set x X1;
 			set y X2;
 		};
 
-		fun :: get2 (inc :: x y)  {
+		fun(#class) get2 (inc :: x y)  {
 			set x (+ X1 inc);
 			set y (+ X2 inc);
 		};
@@ -60,9 +60,9 @@
 	else { printf "OK: d=%d\n" d }
 
 	class X [ x, y ] {
-		fun ::f(a :: b c) { b := (+ a 10); c := (+ a 20) }
+		fun(#class) f(a :: b c) { b := (+ a 10); c := (+ a 20) }
 
-		fun :*new(z) {
+		fun(#classinst) new(z) {
 			## multi-variable assignment with return variables to member variables
 			[self.x, self.y] := (X:f z)
 			return self;
@@ -83,7 +83,7 @@
 
 
 ## create a new binary operator message returning two output values
-fun Number: // (x :: quo rem) {
+fun Number:// (x :: quo rem) {
         quo := (/ self x)
         rem := (- self (* quo x))
 }
diff --git a/t/run.sh b/t/run.sh
index bcc5e83..8beba21 100644
--- a/t/run.sh
+++ b/t/run.sh
@@ -3,4 +3,9 @@
 ## program crashes or exits without an error message.
 echo RUN "[$@]"
 ($@ 2>&1 || echo "ERROR: exited with $?") | grep -E '^ERROR:' && exit 1
+##[ "x$MEMCHECK" = "xyes" ] && {
+##	[ -x /usr/bin/valgrind ] && {
+##		valgrind --leak-check=full --show-reachable=yes --track-fds=yes --log-file=/tmp/x "$@" 2>&1
+##	}
+##}
 exit 0
diff --git a/t/var-01.hcl b/t/var-01.hcl
index ea2b9b0..21aa01a 100644
--- a/t/var-01.hcl
+++ b/t/var-01.hcl
@@ -58,7 +58,7 @@ x
 
 class T [ j ] {
 
-	fun :* new() {
+	fun(#classinst) new() {
 		set j 99
 		return self
 	}
diff --git a/t/var-5001.err b/t/var-5001.err
index 39353dc..6421519 100644
--- a/t/var-5001.err
+++ b/t/var-5001.err
@@ -1,5 +1,5 @@
 defclass A [ a ] {
-	fun :* init1() {
+	fun(#ci) init1() {
 		| b |
 		set b (+ 1 2);
 		set a b;
@@ -15,7 +15,7 @@ defclass A [ a ] {
 		printf ">>> %d\n" j;
 	}
 
-	fun :* init2() {
+	fun(#ci) init2() {
 		| b |
 		set b (+ 10 20);
 		set a b;
@@ -26,7 +26,7 @@ defclass A [ a ] {
 
 ---
 
-fun String length() { ##ERROR: syntax error - no argument list
+fun String length() { ##ERROR: syntax error - 'String' not followed by ( but followed by 'length'
 }
 
 ---
diff --git a/t/var-5004.err b/t/var-5004.err
index 464a1f7..6db00fe 100644
--- a/t/var-5004.err
+++ b/t/var-5004.err
@@ -1,2 +1,66 @@
 fun self.x() { ##ERROR: syntax error - invalid function name 'self.x' for 'fun'
 };
+
+---
+
+fun if() { ##ERROR: syntax error - invalid function name 'if' for 'fun'
+};
+
+---
+
+fun a if() { ##ERROR: syntax error - 'a' not followed by ( but followed by 'if'
+};
+
+---
+
+fun a:b if() { ##ERROR: syntax error - 'b' not followed by ( but followed by 'if'
+};
+
+---
+
+fun x (x :: 20) { ##ERROR: syntax error - invalid return variable '20' for 'fun'
+}
+
+---
+fun x (x :: if) { ##ERROR: syntax error - invalid return variable 'if' for 'fun'
+}
+
+---
+
+fun x (x :: self.y) { ##ERROR: syntax error - invalid return variable 'self.y' for 'fun'
+}
+
+---
+
+fun x (x :: z z) { ##ERROR: syntax error - duplicate return variable 'z' for 'fun'
+}
+
+---
+
+fun x (x 20) { ##ERROR: syntax error - invalid argument name '20' for 'fun'
+}
+
+---
+
+fun x (+) { ##ERROR: syntax error - invalid argument name '+' for 'fun'
+}
+
+---
+
+fun x (a while) { ##ERROR: syntax error - invalid argument name 'while' for 'fun'
+}
+
+---
+
+fun x (a b a) { ##ERROR: syntax error - duplicate argument name 'a' for 'fun'
+}
+
+---
+
+fun x (... a) { ##ERROR: syntax error - unexpected token 'a' after '...' for 'fun'
+}
+
+---
+
+fun x (... : a) { ##ERROR: syntax error - : disallowed
+}