Index: library/nx/nx.tcl
===================================================================
diff -u -r74b7a4066526ff5f5a8080ed907f71c9ed5c7700 -r8776580a91fa04fd52378dd37143f6c27769c8ab
--- library/nx/nx.tcl	(.../nx.tcl)	(revision 74b7a4066526ff5f5a8080ed907f71c9ed5c7700)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 8776580a91fa04fd52378dd37143f6c27769c8ab)
@@ -229,19 +229,16 @@
   ######################################################################
 
   ::nsf::method::create Class method {
-    name arguments:parameter,0..* -checkalways:switch -returns body -precondition -postcondition
+    name arguments:parameter,0..* -checkalways:switch -returns body
   } {
-    set conditions [list]
-    if {[info exists precondition]}  {lappend conditions -precondition  $precondition}
-    if {[info exists postcondition]} {lappend conditions -postcondition $postcondition}
     set p [:__resolve_method_path $name]
     set p [dict filter $p script {k v} {expr {$k in {object regObject methodName}}}]
     dict with p {
       #puts "class method $object.$methodName [list $arguments] {...}"
       set r [::nsf::method::create $object \
 		 -checkalways=$checkalways \
 		 {*}[expr {$regObject ne "" ? "-reg-object [list $regObject]" : ""}] \
-		 $methodName $arguments $body {*}$conditions]
+		 $methodName $arguments $body]
       if {$r ne ""} {
 	# the method was not deleted
 	::nsf::method::property $object $r call-protected \
@@ -501,18 +498,15 @@
     #    - "forward"
 
     :public method "object method" {
-      name arguments:parameter,0..* -checkalways:switch -returns body -precondition -postcondition
+      name arguments:parameter,0..* -checkalways:switch -returns body
     } {
-      set conditions [list]
-      if {[info exists precondition]}  {lappend conditions -precondition  $precondition}
-      if {[info exists postcondition]} {lappend conditions -postcondition $postcondition}
       array set "" [:__resolve_method_path -per-object $name]
       # puts "object method $(object).$(methodName) [list $arguments] {...}"
       set r [::nsf::method::create $(object) \
 		 -checkalways=$checkalways \
 		 {*}[expr {$(regObject) ne "" ? "-reg-object [list $(regObject)]" : ""}] \
 		 -per-object \
-		 $(methodName) $arguments $body {*}$conditions]
+		 $(methodName) $arguments $body]
       if {$r ne ""} {
 	# the method was not deleted
 	::nsf::method::property $(object) $r call-protected \
@@ -878,8 +872,6 @@
       return [string trimright "/cls/ [namespace tail $name] [: ::nsf::methods::class::info::method syntax $name]" { }]
     }
     :method "info method type"          {name} {: ::nsf::methods::class::info::method type $name}
-    :method "info method precondition"  {name} {: ::nsf::methods::class::info::method precondition $name}
-    :method "info method postcondition" {name} {: ::nsf::methods::class::info::method postcondition $name}
     :method "info method submethods"    {name} {: ::nsf::methods::class::info::method submethods $name}
     :method "info method returns"       {name} {: ::nsf::methods::class::info::method returns $name}
   }
@@ -903,8 +895,6 @@
       return [string trimright "/obj/ [namespace tail $name] [: ::nsf::methods::object::info::method syntax $name]" { }]
     }
     :method "info object method type"          {name} {: ::nsf::methods::object::info::method type $name}
-    :method "info object method precondition"  {name} {: ::nsf::methods::object::info::method precondition $name}
-    :method "info object method postcondition" {name} {: ::nsf::methods::object::info::method postcondition $name}
     :method "info object method submethods"    {name} {: ::nsf::methods::object::info::method submethods $name}
     :method "info object method returns"       {name} {: ::nsf::methods::object::info::method returns $name}
   }
Index: tests/info-method.test
===================================================================
diff -u -r74b7a4066526ff5f5a8080ed907f71c9ed5c7700 -r8776580a91fa04fd52378dd37143f6c27769c8ab
--- tests/info-method.test	(.../info-method.test)	(revision 74b7a4066526ff5f5a8080ed907f71c9ed5c7700)
+++ tests/info-method.test	(.../info-method.test)	(revision 8776580a91fa04fd52378dd37143f6c27769c8ab)
@@ -67,7 +67,7 @@
   nx::Class create C {
     :method m {x} {return proc-[self proc]}
     :object method mpo {} {return instproc-[self proc]}
-    :method m-with-assertions {} {return proc-[self proc]} -precondition 1 -postcondition 2
+    # :method m-with-assertions {} {return proc-[self proc]} -precondition 1 -postcondition 2
     
     :forward addOne expr 1 +
     :object forward add1 expr 1 +
@@ -81,7 +81,7 @@
   }
   C create c1
   
-  ? {lsort [C info methods -callprotection all]} "a addOne m m-with-assertions s"
+  ? {lsort [C info methods -callprotection all]} "a addOne m s"
   #? {lsort [C info methods]} "a addOne s"
   foreach m [lsort [C info methods -callprotection all]] {
     ? [subst -nocommands {lsort [c1 info lookup methods $m]}] $m
@@ -100,16 +100,16 @@
   
   ? {C info method definition m} {::C public method m x {return proc-[self proc]}}
   ? {C info object method definition mpo} {::C public object method mpo {} {return instproc-[self proc]}}
-  if {$::nsf::config(assertions)} {
-    ? {C info method definition m-with-assertions} \
-	{::C public method m-with-assertions {} {return proc-[self proc]} -precondition 1 -postcondition 2}
-  } else {
-    ? {C info method definition m-with-assertions} \
-	{::C public method m-with-assertions {} {return proc-[self proc]}}
-  }
+  # if {$::nsf::config(assertions)} {
+  #   ? {C info method definition m-with-assertions} \
+  #       {::C public method m-with-assertions {} {return proc-[self proc]} -precondition 1 -postcondition 2}
+  # } else {
+  #   ? {C info method definition m-with-assertions} \
+  #       {::C public method m-with-assertions {} {return proc-[self proc]}}
+  # }
   ? {C info method parameters m} {x}
   ? {nx::Class info method parameters method} \
-      {name arguments:parameter,0..* -checkalways:switch -returns body -precondition -postcondition}
+      {name arguments:parameter,0..* -checkalways:switch -returns body}
   ? {nx::Class info method parameters alias} \
       {methodName -returns {-frame default} cmd}
   # raises currently an error
@@ -138,7 +138,7 @@
   ? {lsort [::nx::Object info lookup methods]} $class_methods
   ? {lsort [::nx::Class info lookup methods]} $class_methods
   ? {lsort [C info lookup methods -source application]} "add1 apo fpo mpo spo"
-  ? {lsort [c1 info lookup methods -source application]} "a addOne foo m m-with-assertions s"
+  ? {lsort [c1 info lookup methods -source application]} "a addOne foo m s"
   ? {lsort [C info lookup methods -source system]} $class_methods
   ? {lsort [c1 info lookup methods -source system]} $object_methods
 
@@ -801,7 +801,7 @@
 nx::test case parametersyntax {
   # a true method
   ? {::nx::Class info method syntax method} \
-      "/cls/ method /name/ /arguments/ ?-checkalways? ?-returns /value/? /body/ ?-precondition /value/? ?-postcondition /value/?"
+      "/cls/ method /name/ /arguments/ ?-checkalways? ?-returns /value/? /body/"
   # a forwarder to ::nsf::relation; definition comes via array ::nsf::parametersyntax
   ? {::nx::Class info method syntax mixin} "/cls/ mixin ?/class .../?|?add /class/?|?delete /class/?"
 
Index: tests/methods.test
===================================================================
diff -u -r17b2bed824041ef05d7739b2151882d5f9ec1f88 -r8776580a91fa04fd52378dd37143f6c27769c8ab
--- tests/methods.test	(.../methods.test)	(revision 17b2bed824041ef05d7739b2151882d5f9ec1f88)
+++ tests/methods.test	(.../methods.test)	(revision 8776580a91fa04fd52378dd37143f6c27769c8ab)
@@ -1084,37 +1084,39 @@
   ? {e1 bar} bar
 }
 
-nx::test case assertion-swallows-result {
+nx::test case xotcl-assertion-swallows-result {
 
-  nx::Class create Edge {
-    :public method foo {} {
-      :configure -xxx 1
-    }
-    :public method bar {} {
-      :configure -xxx 1
-    } -postcondition {{1 == 0}}
-    :create e1
+  package req XOTcl
+
+  xotcl::Class create Edge 
+  Edge instproc foo {} {
+    my set xxx
   }
 
+  Edge instproc bar {} {
+    my set xxx
+  } {} {{1 == 0}}
+
+  Edge create e1
+
   # base case
   ? {catch {e1 foo} errMsg} 1
-  ? {string match "invalid non-positional*" $errMsg} 1
+  ? {string match {can't read "xxx":*} $errMsg} 1
 
   ? {catch {e1 bar} errMsg} 1
-  ? {string match "invalid non-positional*" $errMsg} 1
+  ? {string match {can't read "xxx":*} $errMsg} 1
 
 
   # turn on assertion checking
   nsf::method::assertion e1 check all
 
   # still report error when invariant would not return error
   ? {catch {e1 foo} errMsg} 1
-  ? {string match "invalid non-positional*" $errMsg} 1
+  ? {string match {can't read "xxx":*} $errMsg} 1
 
-  # still report error when postcondition would not return error
+  # still report error when postcondition would return an error
   ? {catch {e1 bar} errMsg} 1
-  ? {string match "invalid non-positional*" $errMsg} 1
-
+  ? {string match {can't read "xxx":*} $errMsg} 1
 }
 
 
Index: tests/parameters.test
===================================================================
diff -u -r74b7a4066526ff5f5a8080ed907f71c9ed5c7700 -r8776580a91fa04fd52378dd37143f6c27769c8ab
--- tests/parameters.test	(.../parameters.test)	(revision 74b7a4066526ff5f5a8080ed907f71c9ed5c7700)
+++ tests/parameters.test	(.../parameters.test)	(revision 8776580a91fa04fd52378dd37143f6c27769c8ab)
@@ -616,7 +616,7 @@
       "query instparams with default, no paramdefs needed"
 
   ? {nx::Class info method parameters method} \
-      "name arguments:parameter,0..* -checkalways:switch -returns body -precondition -postcondition" \
+      "name arguments:parameter,0..* -checkalways:switch -returns body" \
       "query instparams for scripted method 'method'"
   
   ? {nx::Object info method parameters ::nsf::method::forward} \