Index: TODO
===================================================================
diff -u -rc417409d8e77b24b3cb2a8966423452295ed68d8 -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- TODO	(.../TODO)	(revision c417409d8e77b24b3cb2a8966423452295ed68d8)
+++ TODO	(.../TODO)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -5108,117 +5108,19 @@
 Makefile:
 - fix load paths for sublibs (e.g. mongodb) in regression test
 
+nsf.c:
+- added nsf::var::get and "::nx::var get" to provide selector
+  based interface for variable reading (used in slotmethod get
+  of nx::VariableSlot)
 ========================================================================
 TODO:
 - TODO: rename "slotassign" to "slotset"?
 - TODO: update tutorial and migration guide
 
 - why is there no pos/index arg for mixin|filter delete?
 
-- finish nx-property reform
+- finish nx-property reform (merge into master)
 
-- -incremental: setting incremental will promote a property/variable
-   from a non-multivalued one to a multivalued one ->
-   i.e., it becomes 0..*  unconditionally
-
-   if the following is stated (ambiguous, but allowed):
-
-   /obj/ object property -incremental a:1..1 
-
-   we will end up with "a" becoming 0..*, allowing empty strings without
-   this being acknowledged by the definition (even if ambiguous). maybe this is more compelling when
-   setting incremental a posteriori and reconfigure a property/variable.
-
-   suggestion: make the lower bound always respected -> 1..1 becomes
-   1..*, 0..1 becomes 0..*
-
-   alternatively, we can enforce that -incremental can only be used on
-   props/vars explicitly declared multivalued, rather than promoting
-   them silently? 
-
-   >>>
-   Maybe limiting -incremental to props/vars explicitly declared
-   multivalued would be more honest, simply because 0..1/1..1 permit
-   values (any Tcl word) which cannot be turned in to a list rep no
-   way ... so silently attempting to promote them will always have NX
-   throw up.
-
-- at this point, the documentation of variable vs. property (in the
-  man pages and the tutorial) boils down to:
-
-  "property equals variable despite a different default value of
-  nonpos arg -configurable" (and the consequences entailed by this
-  condition -> configure option, slot object).
-
-  (agreed, they also differ slightly by their definition syntaxes,
-  e.g. placement of the default value etc., but this is also more a
-  historical artifact)
-
-  historically, there used to be more differences (no accessors for
-  variable etc.), right now, the largest portions of the their
-  documentation is identical.
-
-  so, I act as the devil's advocate: is it worth keeping both, rather
-  than giving an example of how to use -configurable on
-  property to achieve what is now achieved by variable (or vice versa)?
-
-  one could restate anything written in Section 3.1.2 of the tutorial
-  by substituting occurrences of ":variable" for ":property
-  -configurable false ...". Or, if the notion of variable should take
-  precedence (with the sections being named "non-configurable instance variables"
-  ...) drop property and keep ":variable -configurable false" which
-  literally expressed what is stated in the section headings.
-
-  or, to be on the safe side, make "property" a requirable feature and
-  just keep "variable" for the core API?
-
-  maybe I am wrong, if so, what is a convincing statement/scenario
-  (from the API perspective) to give to the reader of property
-  vs. variable rather than explaining property vs. property
-  -configurable false (or variable vs. variable -configurable false)
-  only? (apparently, i can't think of one)
-
-- incremental: should we add a third operation?
-
-  /obj/ /prop/ get /index/
-
-  right now, we only provide a setter facade (add, delete) for list
-  values, no getter one. Reasons: consistency (per-element getter +
-  setter), a complete getter+setter facade would also allow for
-  switching from a list representation of multivalued values to
-  another one (e.g., some mongodb data structure?) without changing
-  clients of the incremental interface (e.g., which now use [lindex]
-  etc. to retrieve elements from the property-managed list value) ...
-
-  get would behave like (=be implemented with) lindex.
-
- >>>
-    * the typical idiom for set-valued db-results is foreach, not lindex.
-      Is there a convincing use case? from databases one gets a "set" of values
-      accessing the nth one is rather a border case.
-    * We have for variable and relation slots aleady "assign", "get", 
-      "add" and "delete", so "get" is not reasonable naming choice.
-    * The slot interface is extensible. different slot methods of choice can be added via
-      packages. so why bloat the implementation?
-
- >>> (adding discussion item from yesterday)
-
-    * using the argument arity for the conditional dispatch behind the
-      incremental interface leads to the situation that "get" cannot
-      be called directly, other than assign, get, and delete. there is
-      no warning raised, no feedback given to the client.
-    * therefore, should we provide for three modes (as an example):
-
-      - implicit slot interface (arity-based conditional dispatch),
-        allows for refining the slot interface "behind the scenes"-
-      - explicit slot interface: assign + get are "exported" to
-        clients = must be used. there is no convenience way of
-        getting/setting a property/variable (implementation using ensembles).
-      - incremental slot interface: implies explicit and adds "add" +
-        "delete" (downside: every client must use the explicit
-        interface: assign, get, add, delete; upside: no ambiguities
-        such as with get)
-
 - check deactivated tests in tests/serialize.test
   C(One), C(IgnoreAll), C(None2)
   and xlloc fix
Index: generic/nsf.c
===================================================================
diff -u -rc417409d8e77b24b3cb2a8966423452295ed68d8 -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- generic/nsf.c	(.../nsf.c)	(revision c417409d8e77b24b3cb2a8966423452295ed68d8)
+++ generic/nsf.c	(.../nsf.c)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -25775,6 +25775,20 @@
 }
 
 /*
+cmd var::get NsfVarGetCmd {
+  {-argName "-array" -required 0 -nrargs 0}
+  {-argName "object" -required 1 -type object}
+  {-argName "varName" -required 1 -type tclobj}
+}
+*/
+static int
+NsfVarGetCmd(Tcl_Interp *interp, int withArray,
+	     NsfObject *object, Tcl_Obj *varName) {
+
+  return NsfVarSetCmd(interp, withArray, object, varName, NULL);
+}
+
+/*
 cmd var::import NsfVarImportCmd {
   {-argName "object" -type object}
   {-argName "args" -type args}
Index: generic/nsfAPI.decls
===================================================================
diff -u -r85ee1fdb043ed3f82fd272cc004c476c40861fdb -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- generic/nsfAPI.decls	(.../nsfAPI.decls)	(revision 85ee1fdb043ed3f82fd272cc004c476c40861fdb)
+++ generic/nsfAPI.decls	(.../nsfAPI.decls)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -241,6 +241,12 @@
   {-argName "object" -required 1 -type object}
   {-argName "varName" -required 1}
 } {-nxdoc 1}
+cmd "var::get" NsfVarGetCmd {
+  {-argName "-array" -required 0 -nrargs 0}
+  {-argName "object" -required 1 -type object}
+  {-argName "varName" -required 1 -type tclobj}
+} {-nxdoc 1}
+
 cmd "var::import" NsfVarImportCmd {
   {-argName "object" -required 1 -type object}
   {-argName "args" -type args}
Index: generic/nsfAPI.h
===================================================================
diff -u -r85ee1fdb043ed3f82fd272cc004c476c40861fdb -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- generic/nsfAPI.h	(.../nsfAPI.h)	(revision 85ee1fdb043ed3f82fd272cc004c476c40861fdb)
+++ generic/nsfAPI.h	(.../nsfAPI.h)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -281,7 +281,7 @@
     
 
 /* just to define the symbol */
-static Nsf_methodDefinition method_definitions[106];
+static Nsf_methodDefinition method_definitions[107];
   
 static CONST char *method_command_namespace_names[] = {
   "::nsf::methods::object::info",
@@ -415,6 +415,8 @@
   NSF_nonnull(2) NSF_nonnull(4);
 static int NsfVarExistsCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv [])
   NSF_nonnull(2) NSF_nonnull(4);
+static int NsfVarGetCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv [])
+  NSF_nonnull(2) NSF_nonnull(4);
 static int NsfVarImportCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv [])
   NSF_nonnull(2) NSF_nonnull(4);
 static int NsfVarSetCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv [])
@@ -626,6 +628,8 @@
   NSF_nonnull(1);
 static int NsfVarExistsCmd(Tcl_Interp *interp, int withArray, NsfObject *object, CONST char *varName)
   NSF_nonnull(1) NSF_nonnull(3) NSF_nonnull(4);
+static int NsfVarGetCmd(Tcl_Interp *interp, int withArray, NsfObject *object, Tcl_Obj *varName)
+  NSF_nonnull(1) NSF_nonnull(3) NSF_nonnull(4);
 static int NsfVarImportCmd(Tcl_Interp *interp, NsfObject *object, int nobjc, Tcl_Obj *CONST nobjv[])
   NSF_nonnull(1) NSF_nonnull(2);
 static int NsfVarSetCmd(Tcl_Interp *interp, int withArray, NsfObject *object, Tcl_Obj *varName, Tcl_Obj *value)
@@ -775,6 +779,7 @@
  NsfShowStackCmdIdx,
  NsfUnsetUnknownArgsCmdIdx,
  NsfVarExistsCmdIdx,
+ NsfVarGetCmdIdx,
  NsfVarImportCmdIdx,
  NsfVarSetCmdIdx,
  NsfVarUnsetCmdIdx,
@@ -2179,6 +2184,27 @@
 }
 
 static int
+NsfVarGetCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
+  ParseContext pc;
+  (void)clientData;
+
+  if (likely(ArgumentParse(interp, objc, objv, NULL, objv[0], 
+                     method_definitions[NsfVarGetCmdIdx].paramDefs, 
+                     method_definitions[NsfVarGetCmdIdx].nrParameters, 0, NSF_ARGPARSE_BUILTIN,
+                     &pc) == TCL_OK)) {
+    int withArray = (int )PTR2INT(pc.clientData[0]);
+    NsfObject *object = (NsfObject *)pc.clientData[1];
+    Tcl_Obj *varName = (Tcl_Obj *)pc.clientData[2];
+
+    assert(pc.status == 0);
+    return NsfVarGetCmd(interp, withArray, object, varName);
+
+  } else {
+    return TCL_ERROR;
+  }
+}
+
+static int
 NsfVarImportCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
   ParseContext pc;
   (void)clientData;
@@ -3056,7 +3082,7 @@
   }
 }
 
-static Nsf_methodDefinition method_definitions[106] = {
+static Nsf_methodDefinition method_definitions[107] = {
 {"::nsf::methods::class::alloc", NsfCAllocMethodStub, 1, {
   {"objectName", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_Tclobj, NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
 },
@@ -3350,6 +3376,11 @@
   {"object", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_Object, NULL,NULL,"object",NULL,NULL,NULL,NULL,NULL},
   {"varName", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_String, NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
 },
+{"::nsf::var::get", NsfVarGetCmdStub, 3, {
+  {"-array", 0, 0, Nsf_ConvertTo_String, NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL},
+  {"object", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_Object, NULL,NULL,"object",NULL,NULL,NULL,NULL,NULL},
+  {"varName", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_Tclobj, NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
+},
 {"::nsf::var::import", NsfVarImportCmdStub, 2, {
   {"object", NSF_ARG_REQUIRED, 1, Nsf_ConvertTo_Object, NULL,NULL,"object",NULL,NULL,NULL,NULL,NULL},
   {"args", 0, 1, ConvertToNothing, NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
Index: generic/nsfAPI.nxdocindex
===================================================================
diff -u -rccb2c99f6fb6f381dfc7e300584ac08e3d2809d3 -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- generic/nsfAPI.nxdocindex	(.../nsfAPI.nxdocindex)	(revision ccb2c99f6fb6f381dfc7e300584ac08e3d2809d3)
+++ generic/nsfAPI.nxdocindex	(.../nsfAPI.nxdocindex)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -39,6 +39,7 @@
 set ::nxdoc::include(::nsf::current) 1
 set ::nxdoc::include(::nsf::self) 1
 set ::nxdoc::include(::nsf::var::exists) 1
+set ::nxdoc::include(::nsf::var::get) 1
 set ::nxdoc::include(::nsf::var::import) 1
 set ::nxdoc::include(::nsf::var::set) 1
 set ::nxdoc::include(::nsf::var::unset) 1
Index: library/mongodb/tests/nsf-mongo.test
===================================================================
diff -u -r25023d3c048b369645973fdfa125a3705c7f1898 -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- library/mongodb/tests/nsf-mongo.test	(.../nsf-mongo.test)	(revision 25023d3c048b369645973fdfa125a3705c7f1898)
+++ library/mongodb/tests/nsf-mongo.test	(.../nsf-mongo.test)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -5,6 +5,16 @@
 #
 
 package require nsf
+
+puts stderr "PWD [pwd]"
+puts stderr "auto_path $auto_path"
+foreach p [lsort [package names]] {
+   if {![catch {package present $p}]} {
+      set l [format %-15s $p]
+      puts stderr "loaded $l [package ifneeded $p [package require $p]]"
+   }
+}
+
 package require nx::test
 package require nsf::mongo
 
Index: library/nx/nx.tcl
===================================================================
diff -u -r386420862057241aeeaa8034670634b0da02378b -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- library/nx/nx.tcl	(.../nx.tcl)	(revision 386420862057241aeeaa8034670634b0da02378b)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -1211,20 +1211,6 @@
   createBootstrapVariableSlots ::nx::Slot {
   }
 
-  # Define method "value" as a slot forwarder to allow for calling
-  # value-less slot methods like e.g. "get" dispite of the arity-based
-  # forward dispatcher.
-  # ::nx::Slot public method value {obj method prop value:optional pos:optional} {
-  #   if {[info exists pos]} {
-  #     ${:manager} $prop $obj ${:name} $value $pos
-  #   } elseif {[info exists value]} {
-  #     ${:manager} $prop $obj ${:name} $value
-  #   } else {
-  #     ${:manager} $prop $obj ${:name}
-  #   }
-  # }
-  # TODO REMOVEME
-
   ######################################################################
   # configure nx::ObjectParameterSlot
   ######################################################################
@@ -1841,22 +1827,10 @@
     return [string match {*..[n*]} ${:multiplicity}]
   }
 
-  # ::nx::VariableSlot protected method needsForwarder {} {
-  #   #
-  #   # We just forward, when
-  #   #   * "set", "get" and "add" are still untouched, or
-  #   #   * or incremental is specified
-  #   #
-  #   if {[:info lookup method add] ne "::nsf::classes::nx::VariableSlot::add"} {return 1}
-  #   if {[:info lookup method set] ne "::nsf::classes::nx::VariableSlot::set"} {return 1}
-  #   if {[:info lookup method get] ne "::nsf::classes::nx::VariableSlot::get"} {return 1}
-  #   if {[info exists :settername]} {return 1}
-  #   if {!${:incremental}} {return 0}
-  #   #puts stderr "[self] ismultivalued"
-  #   return 1
-  # }
-
-  # TODO: check detailed xotcl2 implications
+  #
+  # When there are accessors defined, we use always the forwarders in
+  # NX. XOTcl2 has a detailed optimization.
+  #
   ::nx::VariableSlot protected method needsForwarder {} {
     return 1
   }
@@ -2070,7 +2044,7 @@
   #  - delete
   ######################################################################
 
-  ::nsf::method::alias ::nx::VariableSlot value=get    ::nsf::var::set
+  ::nsf::method::alias ::nx::VariableSlot value=get    ::nsf::var::get
   ::nsf::method::alias ::nx::VariableSlot value=set    ::nsf::var::set
   
   ::nx::VariableSlot public method value=unset {obj prop} {
@@ -2709,6 +2683,7 @@
   #
   Object create ::nx::var {
     :public object alias exists ::nsf::var::exists
+    :public object alias get ::nsf::var::get
     :public object alias import ::nsf::var::import
     :public object alias set ::nsf::var::set
   }
Index: tests/accessor.test
===================================================================
diff -u -r0aeccfecef90977dbe8f105c4e808f7f5313486f -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- tests/accessor.test	(.../accessor.test)	(revision 0aeccfecef90977dbe8f105c4e808f7f5313486f)
+++ tests/accessor.test	(.../accessor.test)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -55,7 +55,7 @@
     ? {c1 cget -p3a} 3
     ? {c1 p3a get} 3
     ? {c1 configure -p3a 3} ""
-    ? {c1 p3a get 3} 3
+    ? {c1 p3a get 3} {invalid argument '3', maybe too many arguments; should be "value=get ?-array? /object/ /varName/"}
     ? {c1 p3a set 3} 3
     ? {c1 p3a unset} ""
     ? {c1 cget -p3a} {can't read "p3a": no such variable}
Index: tests/alias.test
===================================================================
diff -u -rdd169437c7a701da0063a40978614e6148d71221 -r6ad766595b0095a72fb7b3a1d6d34960a013b464
--- tests/alias.test	(.../alias.test)	(revision dd169437c7a701da0063a40978614e6148d71221)
+++ tests/alias.test	(.../alias.test)	(revision 6ad766595b0095a72fb7b3a1d6d34960a013b464)
@@ -11,7 +11,7 @@
   # The system methods of nx::VariableSlot are either alias or forwarders
   ? {lsort [::nx::VariableSlot info methods -type alias]} {value=get value=set}
   ? {::nx::VariableSlot info method definition value=get} \
-      "::nx::VariableSlot public alias value=get ::nsf::var::set"
+      "::nx::VariableSlot public alias value=get ::nsf::var::get"
 
   # define an alias and retrieve its definition
   set cmd "::nx::Object public alias set ::set"