Index: TODO
===================================================================
diff -u -rf0f51c24f9e80aa5d0b6a20da9afd37339aab02e -r3e2056578f71e9fb14f5c1ee35a9d626747eb285
--- TODO	(.../TODO)	(revision f0f51c24f9e80aa5d0b6a20da9afd37339aab02e)
+++ TODO	(.../TODO)	(revision 3e2056578f71e9fb14f5c1ee35a9d626747eb285)
@@ -3927,6 +3927,14 @@
   correctly.  
 - Extended regression test
 
+nsf.c:
+- added object parameter option "slotinitialize"
+- renamed object parameter option "invokesetter" -> "slotassign"
+- call slot.assign instead of setter of object
+- removed restriction on nosetter/invokesetter: nosetter can 
+  be used in connection with slotassign
+- added regression test for slot.initialize
+
 ========================================================================
 TODO:
 
Index: generic/nsf.c
===================================================================
diff -u -rf0f51c24f9e80aa5d0b6a20da9afd37339aab02e -r3e2056578f71e9fb14f5c1ee35a9d626747eb285
--- generic/nsf.c	(.../nsf.c)	(revision f0f51c24f9e80aa5d0b6a20da9afd37339aab02e)
+++ generic/nsf.c	(.../nsf.c)	(revision 3e2056578f71e9fb14f5c1ee35a9d626747eb285)
@@ -11598,12 +11598,18 @@
   } else if (strncmp(option, "forward", 7) == 0) {
     paramPtr->flags |= NSF_ARG_FORWARD;
 
-  } else if (strncmp(option, "invokesetter", 12) == 0) {
+  } else if (strncmp(option, "slotassign", 10) == 0) {
     if (unlikely(paramPtr->slotObj == NULL)) {
-      return NsfPrintError(interp, "option 'invokesetter' must follow 'slot='");
+      return NsfPrintError(interp, "option 'slotassign' must follow 'slot='");
     }
-    paramPtr->flags |= NSF_ARG_INVOKESETTER;
+    paramPtr->flags |= NSF_ARG_SLOTASSIGN;
 
+  } else if (strncmp(option, "slotinitialize", 14) == 0) {
+    if (unlikely(paramPtr->slotObj == NULL)) {
+      return NsfPrintError(interp, "option 'slotinit' must follow 'slot='");
+    }
+    paramPtr->flags |= NSF_ARG_SLOTINITIALIZE;
+
   } else if ((dotdot = strnstr(option, "..", optionLength))) {
     /* check lower bound */
     if (*option == '0') {
@@ -21213,6 +21219,19 @@
 }
 */
 
+static NsfObject*
+GetSlotObject(Tcl_Interp *interp, Tcl_Obj *slotObj) {
+  NsfObject *slotObject = NULL;
+
+  assert(slotObj != NULL);
+  GetObjectFromObj(interp, slotObj, &slotObject);
+  if (unlikely(slotObject == NULL)) {
+    NsfPrintError(interp, "couldn't resolve slot object %s", ObjStr(slotObj));
+  }
+  return slotObject;
+}
+
+
 static int
 NsfOConfigureMethod(Tcl_Interp *interp, NsfObject *object, int objc, Tcl_Obj *CONST objv[]) {
   int result, i;
@@ -21338,6 +21357,25 @@
 	    &(pc.full_objv[i]));*/
 
     /*
+     * Handling slot initialize
+     */
+    if (paramPtr->flags & NSF_ARG_SLOTINITIALIZE) {
+      NsfObject *slotObject = GetSlotObject(interp, paramPtr->slotObj);
+      
+      if (likely(slotObject != NULL)) {
+	result = NsfCallMethodWithArgs(interp, (Nsf_Object *)slotObject, NsfGlobalObjs[NSF_INITIALIZE],
+					 object->cmdName, 1, NULL, NSF_CSC_IMMEDIATE);
+      }
+      if (result != TCL_OK) {
+	/* 
+	 * The error message was set either by GetSlotObject or by ...CallMethod... 
+	 */
+	Nsf_PopFrameObj(interp, framePtr);
+	goto configure_exit;
+      }
+    }
+    
+    /*
      * Special setter methods for invoking methods calls; handles types
      * "initcmd", "alias" and "forward".
      */
@@ -21579,9 +21617,24 @@
        * is typically a forwarder to the slot object.
        */
 
-      if (paramPtr->flags & NSF_ARG_INVOKESETTER) {
-	result = NsfCallMethodWithArgs(interp, (Nsf_Object *)object, paramPtr->nameObj,
-				       newValue, 1, NULL, NSF_CSC_IMMEDIATE);
+      if (paramPtr->flags & NSF_ARG_SLOTASSIGN) {
+	NsfObject *slotObject = GetSlotObject(interp, paramPtr->slotObj);
+
+	if (likely(slotObject != NULL)) {
+	  Tcl_Obj *ov[2];
+
+	  ov[0] = paramPtr->nameObj;
+	  ov[1] = newValue;
+	  result = NsfCallMethodWithArgs(interp, (Nsf_Object *)slotObject, NsfGlobalObjs[NSF_ASSIGN],
+					 object->cmdName, 3, ov, NSF_CSC_IMMEDIATE);
+	}
+	if (result != TCL_OK) {
+	  /* 
+	   * The error message was set either by GetSlotObject or by ...CallMethod... 
+	   */
+	  Nsf_PopFrameObj(interp, framePtr);
+	  goto configure_exit;
+	}
       } else {
 	Tcl_ObjSetVar2(interp, paramPtr->nameObj, NULL, newValue, TCL_LEAVE_ERR_MSG|TCL_PARSE_PART1);
       }
Index: generic/nsfInt.h
===================================================================
diff -u -ra6e6e5de115f92c579b867bb88323a9916aec4d4 -r3e2056578f71e9fb14f5c1ee35a9d626747eb285
--- generic/nsfInt.h	(.../nsfInt.h)	(revision a6e6e5de115f92c579b867bb88323a9916aec4d4)
+++ generic/nsfInt.h	(.../nsfInt.h)	(revision 3e2056578f71e9fb14f5c1ee35a9d626747eb285)
@@ -415,17 +415,18 @@
 #define NSF_ARG_UNNAMED			0x080000
 #define NSF_ARG_IS_RETURNVALUE		0x100000
 #define NSF_ARG_NOLEADINGDASH		0x200000
-#define NSF_ARG_INVOKESETTER		0x400000
+#define NSF_ARG_SLOTASSIGN		0x400000
+#define NSF_ARG_SLOTINITIALIZE		0x800000
 
 /* method invocations */
 #define NSF_ARG_METHOD_INVOCATION	     (NSF_ARG_ALIAS|NSF_ARG_FORWARD|NSF_ARG_INITCMD)
 
 /* Disallowed parameter options */
-#define NSF_DISALLOWED_ARG_METHOD_PARAMETER  (NSF_ARG_METHOD_INVOCATION|NSF_ARG_NOCONFIG|NSF_ARG_INVOKESETTER)
+#define NSF_DISALLOWED_ARG_METHOD_PARAMETER  (NSF_ARG_METHOD_INVOCATION|NSF_ARG_NOCONFIG|NSF_ARG_SLOTASSIGN|NSF_ARG_SLOTINITIALIZE)
 #define NSF_DISALLOWED_ARG_SETTER	     (NSF_ARG_SWITCH|NSF_ARG_SUBST_DEFAULT|NSF_DISALLOWED_ARG_METHOD_PARAMETER)
 /*#define NSF_DISALLOWED_ARG_OBJECT_PARAMETER  (NSF_ARG_SWITCH)*/
 #define NSF_DISALLOWED_ARG_OBJECT_PARAMETER  0
-#define NSF_DISALLOWED_ARG_VALUECHECK	     (NSF_ARG_SUBST_DEFAULT|NSF_ARG_METHOD_INVOCATION|NSF_ARG_SWITCH|NSF_ARG_CURRENTLY_UNKNOWN|NSF_ARG_INVOKESETTER)
+#define NSF_DISALLOWED_ARG_VALUECHECK	     (NSF_ARG_SUBST_DEFAULT|NSF_ARG_METHOD_INVOCATION|NSF_ARG_SWITCH|NSF_ARG_CURRENTLY_UNKNOWN|NSF_ARG_SLOTASSIGN|NSF_ARG_SLOTINITIALIZE)
 
 
 /* flags for ParseContext */
@@ -603,7 +604,7 @@
 typedef enum {
   NSF_EMPTY, NSF_ZERO, NSF_ONE,
   /* methods called internally */
-  NSF_CONFIGURE, 
+  NSF_CONFIGURE, NSF_INITIALIZE, NSF_ASSIGN,
   /* var names */
   NSF_AUTONAMES, NSF_DEFAULTMETACLASS, NSF_DEFAULTSUPERCLASS, 
   NSF_ALIAS_ARRAY,
@@ -624,7 +625,7 @@
 char *NsfGlobalStrings[] = {
   "", "0", "1", 
   /* methods called internally */
-  "configure", 
+  "configure", "initialize", "assign",
   /* var names */
   "__autonames", "__default_metaclass", "__default_superclass", 
   "::nsf::alias",
Index: library/nx/nx.tcl
===================================================================
diff -u -rb9c5646036aa10f76ce20f8360a1d8c823ef2355 -r3e2056578f71e9fb14f5c1ee35a9d626747eb285
--- library/nx/nx.tcl	(.../nx.tcl)	(revision b9c5646036aa10f76ce20f8360a1d8c823ef2355)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 3e2056578f71e9fb14f5c1ee35a9d626747eb285)
@@ -1538,6 +1538,7 @@
     {-forObjectParameter 0}
   } {
     set options ""
+    set slotObject ""
     if {[info exists :type]} {
       set type ${:type}
       if {$type eq "switch" && !$forObjectParameter} {set type boolean}
@@ -1553,18 +1554,17 @@
 			     "alnum" "alpha" "ascii" "control" "digit" "double" \
 			     "false" "graph" "lower" "print" "punct" "space" "true" \
 			     "wideinteger" "wordchar" "xdigit" ]} {
-	  lappend options slot=[::nsf::self]
+	  lappend options slot=[::nsf::self] 
 	}
       }
     } elseif {[:info lookup method assign] ne "::nsf::classes::nx::VariableSlot::assign"} {
-      # In case the "assign method" has changed, forward variable
-      # setting in configure (e.g. called during initialization of
-      # object parameters) to the slot.
-      if {${:accessor} == 0} {
-	error "parameter ${:name}: option 'noaccessor' cannot be used together with required accessor (assign method)" 
-      }
-      lappend options slot=[::nsf::self] invokesetter
+      # In case the "assign method" was provided, ask nsf to call it directly
+      lappend options slot=[::nsf::self] slotassign
     }
+    if {[:info lookup method initialize] ne "" && $forObjectParameter} {
+      if {"slot=[::nsf::self]" ni $options} {lappend options slot=[::nsf::self]}
+      lappend options slotinitialize
+    }
     if {[info exists :arg]} {lappend options arg=${:arg}}
     if {${:required}} {
       lappend options required
Index: tests/parameters.test
===================================================================
diff -u -r6a3cd1a111aa693839ec3d788262ce18be74bf91 -r3e2056578f71e9fb14f5c1ee35a9d626747eb285
--- tests/parameters.test	(.../parameters.test)	(revision 6a3cd1a111aa693839ec3d788262ce18be74bf91)
+++ tests/parameters.test	(.../parameters.test)	(revision 3e2056578f71e9fb14f5c1ee35a9d626747eb285)
@@ -2347,14 +2347,17 @@
   ? [list $o eval {info exists :baz}] 1
   ? {set ::slotcalls} 2
   ? [list $o baz] "test" 
+  ? {Foo info method exists baz} 1
 
 } 
 
 
 #
-# Test incompatible forwarding to slot vs. noaccessor
+# Test forwarding to slot vs. noaccessor
 #
 nx::Test case forward-to-assign {
+  set ::slotcalls 0
+
   ? {nx::Class create Foo {
     :property bar:noaccessor {
       :public method assign { object property value } {
@@ -2365,7 +2368,8 @@
   } "::Foo"
 
   # call without default, without object parameter value
-  ? {Foo new} "parameter bar: option 'noaccessor' cannot be used together with required accessor (assign method)"
+  ? {catch {Foo new}} 0
+  ? {set ::slotcalls} 0
 
   # test cases for default
   nx::Class create Foo {
@@ -2378,8 +2382,34 @@
   }
 
   # call with default, without object parameter value
-  ? {Foo new} "parameter baz: option 'noaccessor' cannot be used together with required accessor (assign method)"
+  ? {catch {Foo new}} 0
+  ? {set ::slotcalls} 1
 
   # call with default, with object parameter value
-  ? {Foo new -baz "test"} "parameter baz: option 'noaccessor' cannot be used together with required accessor (assign method)"
-} 
+  ? {catch {Foo new -baz "test"}} 0
+  ? {set ::slotcalls} 2
+  ? {Foo info method exists baz} 0
+}
+
+
+#
+# Test slot initialize 
+#
+nx::Test case forward-to-incremental {
+  set ::slotcalls 0
+
+  ? {nx::Class create Foo {
+    :property bar {
+      :public method initialize { object } {
+	incr ::slotcalls 1
+      }
+    }}
+  } "::Foo"
+
+  # initialize is supposed to be called regardless of some default
+  ? {catch {Foo new}} 0
+  ? {set ::slotcalls} 1
+
+}
+
+