Index: generic/predefined.h
===================================================================
diff -u -r4dd2595d98574faaac87f5dd33b542516fdff5df -r2111020b49da8ce57758e51accf0b6073037f0d2
--- generic/predefined.h	(.../predefined.h)	(revision 4dd2595d98574faaac87f5dd33b542516fdff5df)
+++ generic/predefined.h	(.../predefined.h)	(revision 2111020b49da8ce57758e51accf0b6073037f0d2)
@@ -128,7 +128,8 @@
 "$domain $forwarder $name -default [$manager defaultmethods] $manager %1 %self %proc}\n"
 "::xotcl::MetaSlot create ::xotcl::InfoSlot\n"
 "createBootstrapAttributeSlots ::xotcl::InfoSlot {\n"
-"{multivalued true}}\n"
+"{multivalued true}\n"
+"{elementtype ::xotcl::Class}}\n"
 "::xotcl::relation ::xotcl::InfoSlot superclass ::xotcl::Slot\n"
 "::xotcl::InfoSlot instproc get {obj prop} {$obj info $prop}\n"
 "::xotcl::InfoSlot instproc add {obj prop value {pos 0}} {\n"
@@ -137,8 +138,19 @@
 "$obj $prop [linsert [$obj info $prop] $pos $value]}\n"
 "::xotcl::InfoSlot instproc delete {-nocomplain:switch obj prop value} {\n"
 "set old [$obj info $prop]\n"
-"set p [lsearch -glob $old $value]\n"
-"if {$p>-1} {$obj $prop [lreplace $old $p $p]} else {\n"
+"if {[string first * $value] > -1 || [string first \\[ $value] > -1} {\n"
+"if {[my elementtype] ne \"\" && ![string match ::* $value]} {\n"
+"set value ::$value}\n"
+"return [$obj $prop [lsearch -all -not -glob -inline $old $value]]} elseif {[my elementtype] ne \"\"} {\n"
+"if {[string first :: $value] == -1} {\n"
+"if {![my isobject $value]} {\n"
+"error \"$value does not appear to be an object\"}\n"
+"set value [$value self]}\n"
+"if {![$value isclass [my elementtype]]} {\n"
+"error \"$value does not appear to be of type [my elementtype]\"}}\n"
+"set p [lsearch -exact $old $value]\n"
+"if {$p > -1} {\n"
+"$obj $prop [lreplace $old $p $p]} else {\n"
 "error \"$value is not a $prop of $obj (valid are: $old)\"}}\n"
 "::xotcl::MetaSlot alloc ::xotcl::InterceptorSlot\n"
 "::xotcl::relation ::xotcl::InterceptorSlot superclass ::xotcl::InfoSlot\n"
@@ -156,9 +168,9 @@
 "::xotcl::InfoSlot create ::xotcl::Object::slot::class\n"
 "::xotcl::alias ::xotcl::Object::slot::class assign ::xotcl::relation\n"
 "::xotcl::InterceptorSlot create ::xotcl::Object::slot::mixin\n"
-"::xotcl::InterceptorSlot create ::xotcl::Object::slot::filter\n"
+"::xotcl::InterceptorSlot create ::xotcl::Object::slot::filter -elementtype \"\"\n"
 "::xotcl::InterceptorSlot create ::xotcl::Class::slot::instmixin\n"
-"::xotcl::InterceptorSlot create ::xotcl::Class::slot::instfilter\n"
+"::xotcl::InterceptorSlot create ::xotcl::Class::slot::instfilter -elementtype \"\"\n"
 "::xotcl::MetaSlot create ::xotcl::Attribute -superclass ::xotcl::Slot\n"
 "createBootstrapAttributeSlots ::xotcl::Attribute {\n"
 "{value_check once}\n"
@@ -316,10 +328,7 @@
 "if {[::xotcl::my ismixin $cl]} {return 1}\n"
 "::xotcl::my istype $cl}\n"
 "::xotcl::Class instproc allinstances {} {\n"
-"set set [::xotcl::my info instances]\n"
-"foreach sc [::xotcl::my info subclass] {\n"
-"eval lappend set [$sc allinstances]}\n"
-"return $set}\n"
+"return [::xotcl::my info instances -closure]}\n"
 "::xotcl::Object proc unsetExitHandler {} {\n"
 "::xotcl::Object proc __exitHandler {} {\n"
 ";}}\n"
@@ -331,9 +340,9 @@
 "proc ::xotcl::__exitHandler {} {\n"
 "::xotcl::Object __exitHandler}\n"
 "::xotcl::Object instproc abstract {methtype methname arglist} {\n"
-"if {$methtype ne \"proc\" && $methtype ne \"instproc\"} {\n"
+"if {$methtype ne \"proc\" && $methtype ne \"instproc\" && $methtype ne \"method\"} {\n"
 "error \"invalid method type '$methtype', \\\n"
-"must be either 'proc' or 'instproc'.\"}\n"
+"must be either 'proc', 'instproc' or 'method'.\"}\n"
 "::xotcl::my $methtype $methname $arglist \"\n"
 "if {!\\[::xotcl::self isnextcall\\]} {\n"
 "error \\\"Abstract method $methname $arglist called\\\"} else {::xotcl::next}\n"
@@ -370,7 +379,7 @@
 "$cl instinvar [$origin info instinvar]\n"
 "$cl instfilter [$origin info instfilter -guards]\n"
 "$cl instmixin [$origin info instmixin]\n"
-"my copyNSVarsAndCmds ::xotcl::classes::$origin ::xotcl::classes::$dest} else {\n"
+"my copyNSVarsAndCmds ::xotcl::classes$origin ::xotcl::classes$dest} else {\n"
 "set obj [[$origin info class] create $dest -noinit]}\n"
 "$obj invar [$origin info invar]\n"
 "$obj check [$origin info check]\n"
@@ -391,7 +400,6 @@
 "if {$cmds ne \"\"} {\n"
 "foreach cmd $cmds {\n"
 "foreach {op def} $cmd break\n"
-"$origin trace remove variable $var $op $def\n"
 "if {[lindex $def 0] eq $origin} {\n"
 "set def [concat $dest [lrange $def 1 end]]}\n"
 "$dest trace add variable $var $op $def}}}}\n"
@@ -575,8 +583,7 @@
 "return $v}\n"
 "::xotcl::Object instproc method {name arguments body} {\n"
 "my proc name $arguments $body				}\n"
-"::xotcl::Class instproc method {\n"
-"-per-object:switch name arguments body} {\n"
+"::xotcl::Class instproc method {-per-object:switch name arguments body} {\n"
 "if {${per-object}} {\n"
 "my proc $name $arguments $body} else {\n"
 "my instproc $name $arguments $body}}\n"