Index: TODO
===================================================================
diff -u -r7495af656ca04a32826ecb0b6e207f886eaaa7f8 -r2b56284a45054d5136ddfb67343a70655aba5666
--- TODO	(.../TODO)	(revision 7495af656ca04a32826ecb0b6e207f886eaaa7f8)
+++ TODO	(.../TODO)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -4068,9 +4068,22 @@
 
 - updated 34 copyright notices
 
+nsf.c:
+- extended nsf::method::delete to handle ensemble names
+
+nx.tcl:
+- added tk/incr-tcl style cget methods on class/object levels.
+- improve copy handling with other child-types of the slot container working
+- make sure to ignore non-slot-type objects in slot introspection
+- worked on regression test until "methods.test". others are missing, 
+  but maybe reconsideration
+  
 ========================================================================
 TODO:
-- handling of method names in nsfAPI.h. The following
+- maybe revise class/object level cgets by implementing a global method
+
+- check for potential simplications in scripts for nsf::method::delete
+- handling of method names in error messages from nsfAPI.h. The following
   ? {o __alloc x} {method __alloc not dispatched on valid class}
   should be
   ? {o __alloc x} {method alloc not dispatched on valid class}
Index: generic/nsf.c
===================================================================
diff -u -r7495af656ca04a32826ecb0b6e207f886eaaa7f8 -r2b56284a45054d5136ddfb67343a70655aba5666
--- generic/nsf.c	(.../nsf.c)	(revision 7495af656ca04a32826ecb0b6e207f886eaaa7f8)
+++ generic/nsf.c	(.../nsf.c)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -941,12 +941,14 @@
 NsfDeleteObject(Tcl_Interp *interp, Nsf_Object *object) {
   return DispatchDestroyMethod(interp, (NsfObject *)object, 0);
 }
+
 EXTERN int
 NsfRemoveObjectMethod(Tcl_Interp *interp, Nsf_Object *object1, CONST char *methodName) {
   NsfObject *object = (NsfObject *) object1;
 
-  NsfObjectMethodEpochIncr("NsfRemoveObjectMethod");
+  /*fprintf(stderr, "... NsfRemoveObjectMethod %s %s\n", ObjectName(object), methodName);*/
 
+  NsfObjectMethodEpochIncr("NsfRemoveObjectMethod");
   AliasDelete(interp, object->cmdName, methodName, 1);
 
 #if defined(NSF_WITH_ASSERTIONS)
@@ -964,16 +966,17 @@
   }
   return TCL_OK;
 }
+
 EXTERN int
 NsfRemoveClassMethod(Tcl_Interp *interp, Nsf_Class *class, CONST char *methodName) {
   NsfClass *cl = (NsfClass *) class;
   int rc;
 #if defined(NSF_WITH_ASSERTIONS)
   NsfClassOpt *opt = cl->opt;
 #endif
+  /*fprintf(stderr, "... NsfRemoveClassMethod %s %s\n", ClassName(class), methodName);*/
 
   NsfInstanceMethodEpochIncr("NsfRemoveClassMethod");
-
   AliasDelete(interp, class->object.cmdName, methodName, 0);
 
 #if defined(NSF_WITH_ASSERTIONS)
@@ -12518,7 +12521,6 @@
      * Both, args and body are empty strings. This means we should delete the
      * method.
      */
-
     if (RUNTIME_STATE(interp)->exitHandlerDestroyRound == NSF_EXITHANDLER_OFF) {
       /*
        * Don't delete methods via scripting during shutdown
@@ -13381,7 +13383,8 @@
   Tcl_DString ds, *dsPtr = &ds;
   int fullQualPattern = (pattern && *pattern == ':');
 
-  /*fprintf(stderr, "AddSlotObjects parent %s prefix %s\n", ObjectName(parent), prefix);*/
+  /*fprintf(stderr, "AddSlotObjects parent %s prefix %s type %p %s\n", 
+    ObjectName(parent), prefix, type, type ? ClassName(type) : "");*/
 
   DSTRING_INIT(dsPtr);
   Tcl_DStringAppend(dsPtr, ObjectName(parent), -1);
@@ -19414,9 +19417,45 @@
 static int
 NsfMethodDeleteCmd(Tcl_Interp *interp, NsfObject *object, int withPer_object,
 		   Tcl_Obj *methodNameObj) {
-  return NsfMethodCreateCmd(interp, object, 0, withPer_object, NULL, methodNameObj,
-			    NsfGlobalObjs[NSF_EMPTY],  NsfGlobalObjs[NSF_EMPTY],
-			    NULL, NULL);
+
+  NsfObject *regObject, *defObject;
+  CONST char *methodName1 = NULL;
+  NsfClass *cl = withPer_object == 0 && NsfObjectIsClass(object) ? (NsfClass *)object : NULL;
+  int fromClassNS = cl != NULL, result;
+  Tcl_DString ds, *dsPtr = &ds;
+  Tcl_Command cmd;
+
+  Tcl_DStringInit(dsPtr);
+
+  cmd = ResolveMethodName(interp, cl ? cl->nsPtr : object->nsPtr, methodNameObj,
+			  dsPtr, &regObject, &defObject, &methodName1, &fromClassNS);
+
+  /*fprintf(stderr,
+	  "NsfMethodDeleteCmd method %s '%s' object %p regObject %p defObject %p cl %p fromClass %d cmd %p\n",
+	  ObjStr(methodNameObj), methodName1, object, regObject, defObject, cl, fromClassNS, cmd);*/
+
+  if (cmd) {
+    methodName1 = Tcl_GetCommandName(interp, cmd);
+    if (defObject) {
+      cl = withPer_object == 0 && NsfObjectIsClass(defObject) ? (NsfClass *)defObject : NULL;
+    } else {
+      defObject = object;
+    }
+
+    result = cl ?
+      NsfRemoveClassMethod(interp,  (Nsf_Class *)defObject, methodName1) :
+      NsfRemoveObjectMethod(interp, (Nsf_Object *)defObject, methodName1);
+
+  } else {
+    result = NsfPrintError(interp, "%s: %s method '%s' does not exist",
+			   ObjectName(object), 
+			   withPer_object ? "object specific" : "instance",
+			   ObjStr(methodNameObj));
+  }
+
+  Tcl_DStringFree(dsPtr);
+
+  return result;
 }
 
 /*
Index: library/mongodb/README
===================================================================
diff -u -rebba70b7b0b296de45cb263fa850913ac8711a27 -r2b56284a45054d5136ddfb67343a70655aba5666
--- library/mongodb/README	(.../README)	(revision ebba70b7b0b296de45cb263fa850913ac8711a27)
+++ library/mongodb/README	(.../README)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -9,7 +9,8 @@
 Compile or obtain the mongo-c-driver (client interface)
 
 Assume, Tcl is under /usr/local/ns/lib and the mongo-c-driver is under
-/usr/local/src/mongo-c-driver/, then configre the nsf interface via 
+/usr/local/src/mongo-c-driver/, then configure the nsf interface via the
+following command from nsf*/library/mongodb/  
 
    ./configure --with-tcl=/usr/local/ns/lib --with-nsf=../../ \
    	       --with-mongo=/usr/local/src/mongo-c-driver/src/,/usr/local/src/mongo-c-driver
Index: library/mongodb/example-nsf-mongo.tcl
===================================================================
diff -u -r9248d253eb37bcefbfa38a1d86df306f40922444 -r2b56284a45054d5136ddfb67343a70655aba5666
--- library/mongodb/example-nsf-mongo.tcl	(.../example-nsf-mongo.tcl)	(revision 9248d253eb37bcefbfa38a1d86df306f40922444)
+++ library/mongodb/example-nsf-mongo.tcl	(.../example-nsf-mongo.tcl)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -15,9 +15,12 @@
 if {1} {
   ::mongo::remove $mongoConn tutorial.persons {}
 
-  puts stderr "\nInserting a few tuples"
-  ::mongo::insert $mongoConn tutorial.persons [list name string Joe projects string abc age int 23 \
-						   classes array {0 object {$ref string courses $id oid 1}}]
+  puts "\nInserting a few tuples"
+  if {[catch {
+    ::mongo::insert $mongoConn tutorial.persons [list name string Joe projects string abc age int 23 \
+						     classes array {0 object {$ref string courses $id oid 1}}]
+  }]} {puts "!!! cannot insert dbref;\
+	most likely, the c-driver does not support yet insertion of \$ref, \$id and \$db fields"}
   ::mongo::insert $mongoConn tutorial.persons [list name string Gustaf projects string nsf age int 53]
   ::mongo::insert $mongoConn tutorial.persons [list name string Stefan projects string nsf]
   ::mongo::insert $mongoConn tutorial.persons [list name string Franz info object {x int 203 y int 102} age int 29 projects string gtat]
Index: library/mongodb/mongoAPI.h
===================================================================
diff -u -rc9ef41c49f482a38e89f7cffc54cabf909710425 -r2b56284a45054d5136ddfb67343a70655aba5666
--- library/mongodb/mongoAPI.h	(.../mongoAPI.h)	(revision c9ef41c49f482a38e89f7cffc54cabf909710425)
+++ library/mongodb/mongoAPI.h	(.../mongoAPI.h)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -1,7 +1,27 @@
 
+/*
+ * This source code file was generated by the C-code generator gentclAPI.tcl, 
+ * part of the Next Scripting Framework.
+ */
 
+#if !defined(likely) 
+# if defined(__GNUC__) && __GNUC__ > 2
+/* Use gcc branch prediction hint to minimize cost of e.g. DTrace
+ * ENABLED checks. 
+ */
+#  define unlikely(x) (__builtin_expect((x), 0))
+#  define likely(x) (__builtin_expect((x), 1))
+# else
+#  define unlikely(x) (x)
+#  define likely(x) (x)
+# endif
+#endif
+
+
+
+
 /* just to define the symbol */
-static Nsf_methodDefinition method_definitions[];
+static Nsf_methodDefinition method_definitions[20];
   
 static CONST char *method_command_namespace_names[] = {
   "::mongo"
@@ -74,17 +94,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoCloseIdx].paramDefs, 
                      method_definitions[NsfMongoCloseIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoClose(interp, connPtr,pc.objv[0]);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -93,19 +113,19 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoConnectIdx].paramDefs, 
                      method_definitions[NsfMongoConnectIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     CONST char *withReplica_set = (CONST char *)pc.clientData[0];
     Tcl_Obj *withServer = (Tcl_Obj *)pc.clientData[1];
     int withTimeout = (int )PTR2INT(pc.clientData[2]);
 
     assert(pc.status == 0);
     return NsfMongoConnect(interp, withReplica_set, withServer, withTimeout);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -114,19 +134,19 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoCountIdx].paramDefs, 
                      method_definitions[NsfMongoCountIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *query = (Tcl_Obj *)pc.clientData[2];
 
     assert(pc.status == 0);
     return NsfMongoCount(interp, connPtr, namespace, query);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -135,17 +155,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFSCloseIdx].paramDefs, 
                      method_definitions[NsfMongoGridFSCloseIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfs *gfsPtr = (gridfs *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoGridFSClose(interp, gfsPtr,pc.objv[0]);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -154,19 +174,19 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFSOpenIdx].paramDefs, 
                      method_definitions[NsfMongoGridFSOpenIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *dbname = (CONST char *)pc.clientData[1];
     CONST char *prefix = (CONST char *)pc.clientData[2];
 
     assert(pc.status == 0);
     return NsfMongoGridFSOpen(interp, connPtr, dbname, prefix);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -175,18 +195,18 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFSRemoveFileIdx].paramDefs, 
                      method_definitions[NsfMongoGridFSRemoveFileIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfs *gfsPtr = (gridfs *)pc.clientData[0];
     CONST char *filename = (CONST char *)pc.clientData[1];
 
     assert(pc.status == 0);
     return NsfMongoGridFSRemoveFile(interp, gfsPtr, filename);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -195,12 +215,10 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFSStoreFileIdx].paramDefs, 
                      method_definitions[NsfMongoGridFSStoreFileIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfs *gfsPtr = (gridfs *)pc.clientData[0];
     CONST char *filename = (CONST char *)pc.clientData[1];
     CONST char *remotename = (CONST char *)pc.clientData[2];
@@ -209,6 +227,8 @@
     assert(pc.status == 0);
     return NsfMongoGridFSStoreFile(interp, gfsPtr, filename, remotename, contenttype);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -217,17 +237,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileCloseIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileCloseIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoGridFileClose(interp, filePtr,pc.objv[0]);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -236,17 +256,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileGetContentTypeIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileGetContentTypeIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoGridFileGetContentType(interp, filePtr);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -255,17 +275,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileGetContentlengthIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileGetContentlengthIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoGridFileGetContentlength(interp, filePtr);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -274,17 +294,17 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileGetMetaDataIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileGetMetaDataIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
 
     assert(pc.status == 0);
     return NsfMongoGridFileGetMetaData(interp, filePtr);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -293,18 +313,18 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileOpenIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileOpenIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfs *fsPtr = (gridfs *)pc.clientData[0];
     CONST char *filename = (CONST char *)pc.clientData[1];
 
     assert(pc.status == 0);
     return NsfMongoGridFileOpen(interp, fsPtr, filename);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -313,18 +333,18 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileReadIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileReadIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
     int size = (int )PTR2INT(pc.clientData[1]);
 
     assert(pc.status == 0);
     return NsfMongoGridFileRead(interp, filePtr, size);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -333,18 +353,18 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoGridFileSeekIdx].paramDefs, 
                      method_definitions[NsfMongoGridFileSeekIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     gridfile *filePtr = (gridfile *)pc.clientData[0];
     int offset = (int )PTR2INT(pc.clientData[1]);
 
     assert(pc.status == 0);
     return NsfMongoGridFileSeek(interp, filePtr, offset);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -353,12 +373,10 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoIndexIdx].paramDefs, 
                      method_definitions[NsfMongoIndexIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *attributes = (Tcl_Obj *)pc.clientData[2];
@@ -370,6 +388,8 @@
     assert(pc.status == 0);
     return NsfMongoIndex(interp, connPtr, namespace, attributes, withBackground, withDropdups, withSparse, withUnique);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -378,19 +398,19 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoInsertIdx].paramDefs, 
                      method_definitions[NsfMongoInsertIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *values = (Tcl_Obj *)pc.clientData[2];
 
     assert(pc.status == 0);
     return NsfMongoInsert(interp, connPtr, namespace, values);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -399,12 +419,10 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoQueryIdx].paramDefs, 
                      method_definitions[NsfMongoQueryIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *query = (Tcl_Obj *)pc.clientData[2];
@@ -415,6 +433,8 @@
     assert(pc.status == 0);
     return NsfMongoQuery(interp, connPtr, namespace, query, withAtts, withLimit, withSkip);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -423,19 +443,19 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoRemoveIdx].paramDefs, 
                      method_definitions[NsfMongoRemoveIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *condition = (Tcl_Obj *)pc.clientData[2];
 
     assert(pc.status == 0);
     return NsfMongoRemove(interp, connPtr, namespace, condition);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
@@ -444,12 +464,10 @@
   ParseContext pc;
   (void)clientData;
 
-  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
                      method_definitions[NsfMongoUpdateIdx].paramDefs, 
                      method_definitions[NsfMongoUpdateIdx].nrParameters, 0, 1,
-                     &pc) != TCL_OK) {
-    return TCL_ERROR;
-  } else {
+                     &pc) == TCL_OK)) {
     mongo *connPtr = (mongo *)pc.clientData[0];
     CONST char *namespace = (CONST char *)pc.clientData[1];
     Tcl_Obj *cond = (Tcl_Obj *)pc.clientData[2];
@@ -460,10 +478,12 @@
     assert(pc.status == 0);
     return NsfMongoUpdate(interp, connPtr, namespace, cond, values, withUpsert, withAll);
 
+  } else {
+    return TCL_ERROR;
   }
 }
 
-static Nsf_methodDefinition method_definitions[] = {
+static Nsf_methodDefinition method_definitions[20] = {
 {"::mongo::close", NsfMongoCloseStub, 1, {
   {"conn", NSF_ARG_REQUIRED, 1, Nsf_ConvertToPointer, NULL,NULL,"mongo",NULL,NULL,NULL,NULL,NULL}}
 },
Index: library/mongodb/nsfmongo.c
===================================================================
diff -u -rc9ef41c49f482a38e89f7cffc54cabf909710425 -r2b56284a45054d5136ddfb67343a70655aba5666
--- library/mongodb/nsfmongo.c	(.../nsfmongo.c)	(revision c9ef41c49f482a38e89f7cffc54cabf909710425)
+++ library/mongodb/nsfmongo.c	(.../nsfmongo.c)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -643,7 +643,8 @@
   }
 
   bson_finish(b);
-  result = mongo_insert(connPtr, namespace, b);
+  /* for the time being, no write_concern (last arg of mongo_insert()) */
+  result = mongo_insert(connPtr, namespace, b, NULL);
 
   if (result == MONGO_ERROR) {
     result = NsfPrintError(interp, ErrorMsg(connPtr->err));
@@ -735,7 +736,8 @@
   }
  
   BsonAppendObjv(interp, query, objc, objv);
-  mongo_remove(connPtr, namespace, query);
+  /* for the time being, no write_concern (last arg of mongo_remove()) */
+  mongo_remove(connPtr, namespace, query, NULL);
 
   bson_destroy(query);
   return TCL_OK;
@@ -775,7 +777,9 @@
 
   if (withUpsert) {options |= 1;}
   if (withAll) {options |= 2;}
-  mongo_update(connPtr, namespace, cond, values, options);
+
+  /* for the time being, no write_concern (last arg of mongo_update()) */
+  mongo_update(connPtr, namespace, cond, values, options, NULL);
   
   return TCL_OK;
 }
@@ -919,7 +923,7 @@
 NsfMongoGridFileGetMetaData(Tcl_Interp *interp, gridfile* gridFilePtr) {
   bson b;
 
-  b = gridfile_get_metadata(gridFilePtr);
+  gridfile_get_metadata(gridFilePtr, &b);
   Tcl_SetObjResult(interp, BsonToList(interp, b.data, 0));
 
   return TCL_OK;
Index: library/nx/nx.tcl
===================================================================
diff -u -r7495af656ca04a32826ecb0b6e207f886eaaa7f8 -r2b56284a45054d5136ddfb67343a70655aba5666
--- library/nx/nx.tcl	(.../nx.tcl)	(revision 7495af656ca04a32826ecb0b6e207f886eaaa7f8)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -158,7 +158,6 @@
 	  set ensembleName ${object}::$w
 	} 
 	#puts stderr "NX check $scope $object info methods $path @ <$w> cmd=[info command $w] obj?[nsf::object::exists $ensembleName] "
-	#if {[::nsf::directdispatch $object ::nsf::methods::${scope}::info::methods $w] eq ""} 
 	if {![nsf::object::exists $ensembleName]} {
  	  #
 	  # Create dispatch/ensemble object and accessor method (if wanted)
@@ -182,9 +181,16 @@
 	  set type [::nsf::directdispatch $object ::nsf::methods::${scope}::info::method type $w]
 	  set definition [::nsf::directdispatch $object ::nsf::methods::${scope}::info::method definition $w]
 	  if {$scope eq "class"} {
-	    if {$type ne "alias"} {error "can't append to $type"}
-	    if {$definition eq ""} {error "definition must not be empty"}
-	    set object [lindex $definition end]
+	    if {$type eq ""} {
+	      # In case of a copy operation, the ensemble object might
+	      # exist, but the alias might be missing.
+	      ::nsf::method::alias $object $w $ensembleName
+	      set object $ensembleName
+	    } else {
+	      if {$type ne "alias"} {error "can't append to $type"}
+	      if {$definition eq ""} {error "definition must not be empty"}
+	      set object [lindex $definition end]
+	    }
 	  } else {
 	    if {$type ne "object"} {error "can't append to $type"}
 	    if {[llength $definition] != 3} {error "unexpected definition '$definition'"}
@@ -273,7 +279,13 @@
   ######################################################################
 
   # Well, class is not a method defining method either, but a modifier
-  array set ::nsf::methodDefiningMethod {method 1 alias 1 property 1 forward 1 class 1}
+  array set ::nsf::methodDefiningMethod {
+    method 1 alias 1 property 1 forward 1 class 1
+    ::nsf::classes::nx::Class::method 1 ::nsf::classes::nx::Object::method 1
+    ::nsf::classes::nx::Class::alias 1 ::nsf::classes::nx::Object::alias 1
+    ::nsf::classes::nx::Class::property 1 ::nsf::classes::nx::Object::property 1
+    ::nsf::classes::nx::Class::forward 1 ::nsf::classes::nx::Object::forward 1
+  }
 
   ######################################################################
   # Provide method modifiers for ::nx::Object
@@ -523,7 +535,7 @@
   #
   Object public method "delete property" {name} {
     # call explicitly the per-object variant of "info::slotobjects"
-    set slot [: ::nsf::methods::object::info::slotobjects $name]
+    set slot [: ::nsf::methods::object::info::slotobjects -type ::nx::Slot $name]
     if {$slot eq ""} {error "[self]: cannot delete object specific property '$name'"}
     $slot destroy
     nsf::var::unset -nocomplain [self] $name
@@ -537,7 +549,7 @@
       error "[self]: object does not have an instance variable '$name'"
     }
     # call explicitly the per-object variant of "info::slotobejcts"
-    set slot [: ::nsf::methods::object::info::slotobjects $name]
+    set slot [: ::nsf::methods::object::info::slotobjects -type ::nx::Slot $name]
 
     if {$slot ne ""} {
       # it is not a slot-less variable
@@ -660,20 +672,20 @@
     :alias "info precedence"       ::nsf::methods::object::info::precedence
     :method "info slot definition" {{-type:class ::nx::Slot} pattern:optional} {
       set result {}
-      foreach slot [: ::nsf::methods::object::info::slotobjects {*}[current args]] {
+      foreach slot [: ::nsf::methods::object::info::slotobjects -type $type {*}[current args]] {
 	lappend result [$slot getPropertyDefinition]
       }
       return $result
     }
     :method "info slot names" {{-type:class ::nx::Slot} pattern:optional} {
       set result {}
-      foreach slot [: ::nsf::methods::object::info::slotobjects {*}[current args]] {
+      foreach slot [: ::nsf::methods::object::info::slotobjects -type $type {*}[current args]] {
 	lappend result [$slot name]
       }
       return $result
     }
     :method "info slot objects" {{-type:class ::nx::Slot} pattern:optional} {
-      return [: ::nsf::methods::object::info::slotobjects {*}[current args]]
+      return [: ::nsf::methods::object::info::slotobjects -type $type {*}[current args]]
     }
     # "info properties" is a short form of "info slot definition"
     :alias "info properties"     ::nx::Object::slot::__info::slot::definition
@@ -754,7 +766,7 @@
     }
     :method "info slot definition" {{-type ::nx::Slot} -closure:switch -source:optional pattern:optional} {
       set result {}
-      foreach slot [: ::nsf::methods::class::info::slotobjects {*}[current args]] {
+      foreach slot [: ::nsf::methods::class::info::slotobjects -type $type {*}[current args]] {
 	lappend result [$slot getPropertyDefinition]
       }
       return $result
@@ -1161,16 +1173,31 @@
       if {[::nsf::is class ${:domain}]} {
 	::nsf::invalidateobjectparameter ${:domain}
       }
+
       #puts stderr "*** slot destroy of [self], domain ${:domain} per-object ${:per-object}"
       #
-      # delete the accessor
+      # delete the accessors
       #
+      set cgetName "cget -${:name}"
       if {${:per-object}} {
 	if {[${:domain} ::nsf::methods::object::info::method exists ${:name}]} {
 	  ::nsf::method::delete ${:domain} -per-object ${:name}
 	}
-      } elseif {[${:domain} ::nsf::methods::class::info::method exists ${:name}]} {
-	::nsf::method::delete ${:domain} ${:name}
+	if {[${:domain} ::nsf::methods::object::info::method exists ${cgetName}]} {
+	  nsf::method::delete ${:domain} -per-object ${cgetName}
+	  # TODO cleanup
+	  #puts stderr "nsf::method::delete ${:domain} -per-object ${cgetName}"
+	  #puts stderr o-still=[${:domain} ::nsf::methods::object::info::method exists ${cgetName}]
+	}
+      } else {
+	#array set "" [${:domain} eval [list :__resolve_method_path $cgetName]]
+	if {[${:domain} ::nsf::methods::class::info::method exists ${:name}]} {
+	  ::nsf::method::delete ${:domain} ${:name}
+	}
+	if {[${:domain} ::nsf::methods::class::info::method exists ${cgetName}]} {
+	  nsf::method::delete ${:domain} ${cgetName}
+	  #puts stderr c-still=[${:domain} ::nsf::methods::class::info::method exists ${cgetName}]
+	}
       }
     }
     ::nsf::next
@@ -1644,12 +1671,23 @@
   }
 
   ::nx::VariableSlot public method makeAccessor {} {
+    set needsForwarder [:needsForwarder]
+    if {$needsForwarder} {
+      set body "{[self]} get \[self\] ${:name}"
+    } else {
+      set body "return \${:${:name}}"
+    }
 
+    ${:domain} public \
+	[expr {${:per-object} ? "::nsf::classes::nx::Object::method" : "::nsf::classes::nx::Class::method"}] \
+	"cget -${:name}" \
+	{} $body
+
     if {!${:accessor}} {
       #puts stderr "Do not register forwarder ${:domain} ${:name}"
       return 0
     }
-    if {[:needsForwarder]} {
+    if {$needsForwarder} {
       set handle [:makeForwarder]
       :makeIncrementalOperations
     } else {
@@ -2210,16 +2248,18 @@
 	# get class specific slots
 	#
 	if {[::nsf::is class $origin]} {
-	  set slots [$origin ::nsf::methods::class::info::slotobjects]
+	  set slots [$origin ::nsf::methods::class::info::slotobjects -type ::nx::Slot]
 	}
 	#
 	# append object specific slots
 	#
-	foreach slot [$origin ::nsf::methods::object::info::slotobjects] {
+	foreach slot [$origin ::nsf::methods::object::info::slotobjects -type ::nx::Slot] {
 	  lappend slots $slot
 	}
-	#puts stderr "replacing domain and manager from <$origin> to <$dest> in slots <$slots>"
+	puts stderr "replacing domain and manager from <$origin> to <$dest> in slots <$slots>"
 	foreach oldslot $slots {
+	  puts stderr "check slot <$oldslot> class [nsf::relation $oldslot class] s?[$oldslot info has type ::nx::Slot]"
+	  #if {![$oldslot info has type ::nx::Slot]} continue
 	  set container [expr {[$oldslot per-object] ? "per-object-slot" : "slot"}]
 	  set newslot [::nx::slotObj -container $container $dest [namespace tail $oldslot]]
 	  if {[$oldslot domain] eq $origin}   {$newslot domain $dest}
Index: tests/methods.test
===================================================================
diff -u -ra5dfcb547e25f83286793ba9850b988b822adf3e -r2b56284a45054d5136ddfb67343a70655aba5666
--- tests/methods.test	(.../methods.test)	(revision a5dfcb547e25f83286793ba9850b988b822adf3e)
+++ tests/methods.test	(.../methods.test)	(revision 2b56284a45054d5136ddfb67343a70655aba5666)
@@ -170,9 +170,9 @@
   ? {::nsf::dispatch c1 protected_object_alias} "protected_object_alias"
 
   ? {lsort [c1 info methods]} \
-      "plain_object_alias plain_object_forward plain_object_method plain_object_setter public_object_alias public_object_forward public_object_method public_object_setter"
+      "cget plain_object_alias plain_object_forward plain_object_method plain_object_setter public_object_alias public_object_forward public_object_method public_object_setter"
   ? {lsort [C class info methods]} \
-      "plain_object_alias plain_object_forward plain_object_method plain_object_setter public_object_alias public_object_forward public_object_method public_object_setter s3"
+      "cget plain_object_alias plain_object_forward plain_object_method plain_object_setter public_object_alias public_object_forward public_object_method public_object_setter s3"
 }
 
 C destroy
@@ -336,8 +336,8 @@
   }
   ? {C x 1} 1
   ? {C x} 1
-  ? {C info methods} "a"
-  ? {C class info methods} x
+  ? {lsort [C info methods]} "a cget"
+  ? {lsort [C class info methods]} "cget x"
   ? {c1 a b} {expected integer but got "b" for parameter "a"}
 
   set s(C) [C serialize]
@@ -358,8 +358,8 @@
 
   # tests should work as again
   ? {C x} 1
-  ? {C info methods} "a"
-  ? {C class info methods} x
+  ? {lsort [C info methods]} "a cget"
+  ? {lsort [C class info methods]} "cget x"
   ? {c1 a b} {expected integer but got "b" for parameter "a"}  
 }
 
@@ -375,13 +375,13 @@
     :create c1
   }
   
-  ? {::nsf::method::delete C x} "::C: cannot delete method 'x'"
-  ? {::nsf::method::delete C -per-object x} "::C: cannot delete object specific method 'x'"
+  ? {::nsf::method::delete C x} "::C: instance method 'x' does not exist"
+  ? {::nsf::method::delete C -per-object x} "::C: object specific method 'x' does not exist"
   ? {::nsf::method::delete C foo} ""
-  ? {::nsf::method::delete C foo} "::C: cannot delete method 'foo'"
-  ? {::nsf::method::delete C bar} "::C: cannot delete method 'bar'"
+  ? {::nsf::method::delete C foo} "::C: instance method 'foo' does not exist"
+  ? {::nsf::method::delete C bar} "::C: instance method 'bar' does not exist"
   ? {::nsf::method::delete C -per-object bar} ""
-  ? {::nsf::method::delete C -per-object bar} "::C: cannot delete object specific method 'bar'"
+  ? {::nsf::method::delete C -per-object bar} "::C: object specific method 'bar' does not exist"
 }
 
 #
@@ -543,10 +543,10 @@
     :public method "info bar foo" {} {return [namespace current]-[namespace which info]}
   }
 
-  ? {o1 info methods -path} "{info foo} {info bar foo} foo a1 a2"
-  ? {o1 info children} "::o1::info ::o1::per-object-slot"
+  ? {o1 info methods -path} "{info foo} {info bar foo} foo a1 a2 {cget -a2} {cget -a1}"
+  ? {o1 info children} "::o1::info ::o1::per-object-slot ::o1::cget"
 
-  ? {o1 delete method bar} "::o1: cannot delete object specific method 'bar'"
+  ? {o1 delete method bar} "::o1: object specific method 'bar' does not exist"
   # For a1, we have a method and an property. We can delete the
   # method without the slot.
   ? {o1 delete method a1} ""
@@ -559,7 +559,7 @@
   # try to delete the property again:
   ? {o1 delete property a1} "::o1: cannot delete object specific property 'a1'"
 
-  ? {o1 info methods -path} "{info foo} {info bar foo} foo a2"
+  ? {o1 info methods -path} "{info foo} {info bar foo} foo a2 {cget -a2}"
   ? {o1 delete property a2} ""
   ? {o1 info methods -path} "{info foo} {info bar foo} foo"
 
@@ -589,10 +589,10 @@
     :property a2
   }
 
-  ? {C class info methods -path} "{info foo} {info bar foo} foo a1"
-  ? {C info children} "::C::info ::C::slot ::C::per-object-slot"
+  ? {C class info methods -path} "{info foo} {info bar foo} foo a1 {cget -a1}"
+  ? {C info children} "::C::info ::C::slot ::C::per-object-slot ::C::cget"
 
-  ? {C class delete method bar} "::C: cannot delete object specific method 'bar'"
+  ? {C class delete method bar} "::C: object specific method 'bar' does not exist"
 
   ? {C class delete property a1} ""
   ? {C class info methods -path} "{info foo} {info bar foo} foo"
@@ -607,7 +607,7 @@
   ? {C class delete method "info bar foo"} ""
   ? {C class info methods -path} ""
 
-  ? {C info methods} "a2"
+  ? {C info methods} "a2 cget"
   ? {C info slot objects} "::C::slot::a2"
 }
 
@@ -627,10 +627,10 @@
     :public method "info bar foo" {} {return [namespace current]-[namespace which info]}
   }
 
-  ? {C info methods -path} "{info foo} {info bar foo} foo a1"
+  ? {C info methods -path} "{info foo} {info bar foo} foo a1 {cget -a1}"
   ? {C info children} "::C::slot"
 
-  ? {C delete method bar} "::C: cannot delete method 'bar'"
+  ? {C delete method bar} "::C: instance method 'bar' does not exist"
 
   ? {C delete property a1} ""
   ? {C info methods -path} "{info foo} {info bar foo} foo"