Index: TODO
===================================================================
diff -u -rdbd850e0318af673e5f576a8c6fddaa8fef26715 -r8465a13d65cb106deebded93f7fd4956dcb5f84a
--- TODO	(.../TODO)	(revision dbd850e0318af673e5f576a8c6fddaa8fef26715)
+++ TODO	(.../TODO)	(revision 8465a13d65cb106deebded93f7fd4956dcb5f84a)
@@ -5872,8 +5872,7 @@
 
 - Added Rosetta example: https://rosettacode.org/wiki/Inheritance/Single
 
-- return from "nsf::current callinglevel" the value 0 (instead of 1), 
-  when it is called outside of a frame, which has a nsf object associated.
+- new subcommand "nsf::current level", returns empty, if we are not on a nsf frame/level.
 
 ========================================================================
 TODO:
Index: generic/nsf.c
===================================================================
diff -u -rdbd850e0318af673e5f576a8c6fddaa8fef26715 -r8465a13d65cb106deebded93f7fd4956dcb5f84a
--- generic/nsf.c	(.../nsf.c)	(revision dbd850e0318af673e5f576a8c6fddaa8fef26715)
+++ generic/nsf.c	(.../nsf.c)	(revision 8465a13d65cb106deebded93f7fd4956dcb5f84a)
@@ -27463,30 +27463,53 @@
 
 /*
 cmd current NsfCurrentCmd {
-  {-argName "option" -required 0 -typeName "currentoption" -type "proc|method|methodpath|object|class|activelevel|args|activemixin|calledproc|calledmethod|calledclass|callingproc|callingmethod|callingclass|callinglevel|callingobject|filterreg|isnextcall|nextmethod" -default object}
+  {-argName "option" -required 0 -typeName "currentoption" -type "activelevel|activemixin|args|calledclass|calledmethod|calledproc|callingclass|callinglevel|callingmethod|callingobject|callingproc|class|filterreg|isnextcall|level|methodpath|method|nextmethod|object|proc" -default object}
 }
 */
 static int
 NsfCurrentCmd(Tcl_Interp *interp, CurrentoptionIdx_t selfoption) {
-  NsfObject *object = GetSelfObj(interp);
+  NsfObject           *object;
   NsfCallStackContent *cscPtr;
-  Tcl_CallFrame *framePtr;
-  int result = TCL_OK;
+  Tcl_CallFrame       *framePtr;
+  int                  result = TCL_OK;
 
   nonnull_assert(interp != NULL);
 
+  object = GetSelfObj(interp);
+
+  /*
+   * The first two clauses can succeed even it we are outside an nsf context
+   * (no object known). The commands are "nsf::current", "nsf::current
+   * object", "nsf::current level", and "nsf::current activelevel"
+   */
   if (selfoption == CurrentoptionNULL || selfoption == CurrentoptionObjectIdx) {
     if (likely(object != NULL)) {
       Tcl_SetObjResult(interp, object->cmdName);
-      return TCL_OK;
     } else {
-      return NsfNoCurrentObjectError(interp, NULL);
+      result = NsfNoCurrentObjectError(interp, NULL);
     }
+    return result;
   }
 
-  if (unlikely(object == NULL && selfoption != CurrentoptionCallinglevelIdx)) {
-    return NsfNoCurrentObjectError(interp, NULL);
+  if (unlikely(object == NULL)) {
+    if (selfoption == CurrentoptionCallinglevelIdx) {
+      Tcl_SetIntObj(Tcl_GetObjResult(interp), 1);
+    } else if (selfoption == CurrentoptionLevelIdx) {
+      /*
+       * Return empty, if we are not on a nsf level.
+       */
+      Tcl_ResetResult(interp);
+    } else {
+      result = NsfNoCurrentObjectError(interp, NULL);
+    }
+    return result;
   }
+  
+  /*
+   * From here on, we have to be on a valid nsf frame/level, object has to be
+   * know.
+   */
+  assert(object != NULL);
 
   switch (selfoption) {
   case CurrentoptionMethodIdx: /* fall through */
@@ -27586,11 +27609,10 @@
     break;
 
   case CurrentoptionCallinglevelIdx:
-    if (object == NULL) {
-      Tcl_SetIntObj(Tcl_GetObjResult(interp), 0);
-    } else {
-      Tcl_SetObjResult(interp, ComputeLevelObj(interp, CALLING_LEVEL));
-    }
+    /* 
+     * Special case of object==NULL handeled above.
+     */
+    Tcl_SetObjResult(interp, ComputeLevelObj(interp, CALLING_LEVEL));
     break;
 
   case CurrentoptionCallingobjectIdx:
@@ -27618,6 +27640,14 @@
     break;
   }
 
+  case CurrentoptionLevelIdx:
+    /*
+     * We have an "object", therefore we are on a nsf-frame/level. In this
+     * case, "nsf level" behaves like "info level" (without arguments).
+     */
+    Tcl_SetObjResult(interp, Tcl_NewIntObj(Tcl_CallFrame_level(Tcl_Interp_varFramePtr(interp))));
+    break;
+
   case CurrentoptionNextmethodIdx:
     result = FindSelfNext(interp);
     break;
Index: generic/nsfAPI.decls
===================================================================
diff -u -rdbd850e0318af673e5f576a8c6fddaa8fef26715 -r8465a13d65cb106deebded93f7fd4956dcb5f84a
--- generic/nsfAPI.decls	(.../nsfAPI.decls)	(revision dbd850e0318af673e5f576a8c6fddaa8fef26715)
+++ generic/nsfAPI.decls	(.../nsfAPI.decls)	(revision 8465a13d65cb106deebded93f7fd4956dcb5f84a)
@@ -301,7 +301,7 @@
 
 
 cmd current NsfCurrentCmd {
-  {-argName "option" -required 0 -typeName "currentoption" -type "proc|method|methodpath|object|class|activelevel|args|activemixin|calledproc|calledmethod|calledclass|callingproc|callingmethod|callingclass|callinglevel|callingobject|filterreg|isnextcall|nextmethod" -default object}
+  {-argName "option" -required 0 -typeName "currentoption" -type "activelevel|activemixin|args|calledclass|calledmethod|calledproc|callingclass|callinglevel|callingmethod|callingobject|callingproc|class|filterreg|isnextcall|level|methodpath|method|nextmethod|object|proc" -default object}
 } {-nxdoc 1}
 cmd self NsfSelfCmd {
 } {-nxdoc 1}
Index: generic/nsfAPI.h
===================================================================
diff -u -r308a9122fcd679ed416ce55670ea93aab4b87478 -r8465a13d65cb106deebded93f7fd4956dcb5f84a
--- generic/nsfAPI.h	(.../nsfAPI.h)	(revision 308a9122fcd679ed416ce55670ea93aab4b87478)
+++ generic/nsfAPI.h	(.../nsfAPI.h)	(revision 8465a13d65cb106deebded93f7fd4956dcb5f84a)
@@ -142,12 +142,12 @@
   return result;
 }
   
-typedef enum {CurrentoptionNULL, CurrentoptionProcIdx, CurrentoptionMethodIdx, CurrentoptionMethodpathIdx, CurrentoptionObjectIdx, CurrentoptionClassIdx, CurrentoptionActivelevelIdx, CurrentoptionArgsIdx, CurrentoptionActivemixinIdx, CurrentoptionCalledprocIdx, CurrentoptionCalledmethodIdx, CurrentoptionCalledclassIdx, CurrentoptionCallingprocIdx, CurrentoptionCallingmethodIdx, CurrentoptionCallingclassIdx, CurrentoptionCallinglevelIdx, CurrentoptionCallingobjectIdx, CurrentoptionFilterregIdx, CurrentoptionIsnextcallIdx, CurrentoptionNextmethodIdx} CurrentoptionIdx_t;
+typedef enum {CurrentoptionNULL, CurrentoptionActivelevelIdx, CurrentoptionActivemixinIdx, CurrentoptionArgsIdx, CurrentoptionCalledclassIdx, CurrentoptionCalledmethodIdx, CurrentoptionCalledprocIdx, CurrentoptionCallingclassIdx, CurrentoptionCallinglevelIdx, CurrentoptionCallingmethodIdx, CurrentoptionCallingobjectIdx, CurrentoptionCallingprocIdx, CurrentoptionClassIdx, CurrentoptionFilterregIdx, CurrentoptionIsnextcallIdx, CurrentoptionLevelIdx, CurrentoptionMethodpathIdx, CurrentoptionMethodIdx, CurrentoptionNextmethodIdx, CurrentoptionObjectIdx, CurrentoptionProcIdx} CurrentoptionIdx_t;
 
 static int ConvertToCurrentoption(Tcl_Interp *interp, Tcl_Obj *objPtr, Nsf_Param const *pPtr,
 			    ClientData *clientData, Tcl_Obj **outObjPtr) {
   int index, result;
-  static const char *opts[] = {"proc", "method", "methodpath", "object", "class", "activelevel", "args", "activemixin", "calledproc", "calledmethod", "calledclass", "callingproc", "callingmethod", "callingclass", "callinglevel", "callingobject", "filterreg", "isnextcall", "nextmethod", NULL};
+  static const char *opts[] = {"activelevel", "activemixin", "args", "calledclass", "calledmethod", "calledproc", "callingclass", "callinglevel", "callingmethod", "callingobject", "callingproc", "class", "filterreg", "isnextcall", "level", "methodpath", "method", "nextmethod", "object", "proc", NULL};
   (void)pPtr;
   result = Tcl_GetIndexFromObj(interp, objPtr, opts, "currentoption", 0, &index);
   *clientData = (ClientData) INT2PTR(index + 1);
@@ -265,7 +265,7 @@
   {ConvertToCallprotection, "all|public|protected|private"},
   {ConvertToMethodtype, "all|scripted|builtin|alias|forwarder|object|setter|nsfproc"},
   {ConvertToFrame, "method|object|default"},
-  {ConvertToCurrentoption, "proc|method|methodpath|object|class|activelevel|args|activemixin|calledproc|calledmethod|calledclass|callingproc|callingmethod|callingclass|callinglevel|callingobject|filterreg|isnextcall|nextmethod"},
+  {ConvertToCurrentoption, "activelevel|activemixin|args|calledclass|calledmethod|calledproc|callingclass|callinglevel|callingmethod|callingobject|callingproc|class|filterreg|isnextcall|level|methodpath|method|nextmethod|object|proc"},
   {ConvertToMethodproperty, "class-only|call-private|call-protected|debug|deprecated|exists|redefine-protected|returns"},
   {ConvertToRelationtype, "object-mixin|class-mixin|object-filter|class-filter|class|superclass|rootclass"},
   {ConvertToDefinitionsource, "all|application|system"},