Fix DagSink (no nodes slot), add traits.

lang/src/Kernel-Dag.js

@@ -549,10 +549,13 @@ $globals.DagParentNode);
 
 
 
-$core.addClass("DagSink", $globals.DagNode, ["nodes"], "Kernel-Dag");
+$core.addClass("DagSink", $globals.DagNode, [], "Kernel-Dag");
 //>>excludeStart("ide", pragmas.excludeIdeData);
 $globals.DagSink.comment="I am `DagNode` with no direct successors.\x0a\x0aSending `dagChildren:` with empty collection is legal.";
 //>>excludeEnd("ide");
+
+
+$core.addTrait("TDagSink", "Kernel-Dag");
 $core.addMethod(
 $core.method({
 selector: "dagChildren",
@@ -569,7 +572,7 @@ var self=this,$self=this;
 return [];
 
 }; }),
-$globals.DagSink);
+$globals.TDagSink);
 
 $core.addMethod(
 $core.method({
@@ -601,8 +604,134 @@ return self;
 }, function($ctx1) {$ctx1.fill(self,"dagChildren:",{aCollection:aCollection})});
 //>>excludeEnd("ctx");
 }; }),
-$globals.DagSink);
+$globals.TDagSink);
+
+
+$core.addTrait("TDerivedDagChildren", "Kernel-Dag");
+$core.addMethod(
+$core.method({
+selector: "addDagChild:",
+protocol: "accessing",
+//>>excludeStart("ide", pragmas.excludeIdeData);
+args: ["aDagNode"],
+source: "addDagChild: aDagNode\x0a\x09self error: 'Cannot add child for a TDerivedChildren.'",
+referencedClasses: [],
+//>>excludeEnd("ide");
+pragmas: [],
+messageSends: ["error:"]
+}, function ($methodClass){ return function (aDagNode){
+var self=this,$self=this;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+return $core.withContext(function($ctx1) {
+//>>excludeEnd("ctx");
+$self._error_("Cannot add child for a TDerivedChildren.");
+return self;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+}, function($ctx1) {$ctx1.fill(self,"addDagChild:",{aDagNode:aDagNode})});
+//>>excludeEnd("ctx");
+}; }),
+$globals.TDerivedDagChildren);
+
+$core.addMethod(
+$core.method({
+selector: "dagChildren",
+protocol: "accessing",
+//>>excludeStart("ide", pragmas.excludeIdeData);
+args: [],
+source: "dagChildren\x0a\x09self subclassResponsibility",
+referencedClasses: [],
+//>>excludeEnd("ide");
+pragmas: [],
+messageSends: ["subclassResponsibility"]
+}, function ($methodClass){ return function (){
+var self=this,$self=this;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+return $core.withContext(function($ctx1) {
+//>>excludeEnd("ctx");
+$self._subclassResponsibility();
+return self;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+}, function($ctx1) {$ctx1.fill(self,"dagChildren",{})});
+//>>excludeEnd("ctx");
+}; }),
+$globals.TDerivedDagChildren);
+
+$core.addMethod(
+$core.method({
+selector: "dagChildren:",
+protocol: "accessing",
+//>>excludeStart("ide", pragmas.excludeIdeData);
+args: ["aCollection"],
+source: "dagChildren: aCollection\x0a\x09self error: 'Cannot set children of a TDerivedChildren.'",
+referencedClasses: [],
+//>>excludeEnd("ide");
+pragmas: [],
+messageSends: ["error:"]
+}, function ($methodClass){ return function (aCollection){
+var self=this,$self=this;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+return $core.withContext(function($ctx1) {
+//>>excludeEnd("ctx");
+$self._error_("Cannot set children of a TDerivedChildren.");
+return self;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+}, function($ctx1) {$ctx1.fill(self,"dagChildren:",{aCollection:aCollection})});
+//>>excludeEnd("ctx");
+}; }),
+$globals.TDerivedDagChildren);
+
+
+$core.addTrait("TSingleDagChild", "Kernel-Dag");
+$core.addMethod(
+$core.method({
+selector: "dagChild",
+protocol: "accessing",
+//>>excludeStart("ide", pragmas.excludeIdeData);
+args: [],
+source: "dagChild\x0a\x09self subclassResponsibility",
+referencedClasses: [],
+//>>excludeEnd("ide");
+pragmas: [],
+messageSends: ["subclassResponsibility"]
+}, function ($methodClass){ return function (){
+var self=this,$self=this;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+return $core.withContext(function($ctx1) {
+//>>excludeEnd("ctx");
+$self._subclassResponsibility();
+return self;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+}, function($ctx1) {$ctx1.fill(self,"dagChild",{})});
+//>>excludeEnd("ctx");
+}; }),
+$globals.TSingleDagChild);
+
+$core.addMethod(
+$core.method({
+selector: "dagChildren",
+protocol: "accessing",
+//>>excludeStart("ide", pragmas.excludeIdeData);
+args: [],
+source: "dagChildren\x0a\x09^ { self dagChild }",
+referencedClasses: [],
+//>>excludeEnd("ide");
+pragmas: [],
+messageSends: ["dagChild"]
+}, function ($methodClass){ return function (){
+var self=this,$self=this;
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+return $core.withContext(function($ctx1) {
+//>>excludeEnd("ctx");
+return [$self._dagChild()];
+//>>excludeStart("ctx", pragmas.excludeDebugContexts);
+}, function($ctx1) {$ctx1.fill(self,"dagChildren",{})});
+//>>excludeEnd("ctx");
+}; }),
+$globals.TSingleDagChild);
 
+$core.setTraitComposition([{trait: $globals.TDerivedDagChildren}], $globals.TDagSink);
+$core.setTraitComposition([{trait: $globals.TDerivedDagChildren}], $globals.TSingleDagChild);
+$core.setTraitComposition([{trait: $globals.TDagSink}], $globals.DagSink);
 
 $core.addMethod(
 $core.method({

lang/src/Kernel-Dag.st

@@ -164,14 +164,17 @@ dagChildren: aCollection
 ! !
 
 DagNode subclass: #DagSink
-	slots: {#nodes}
+	slots: {}
 	package: 'Kernel-Dag'!
 !DagSink commentStamp!
 I am `DagNode` with no direct successors.
 
 Sending `dagChildren:` with empty collection is legal.!
 
-!DagSink methodsFor: 'accessing'!
+Trait named: #TDagSink
+	package: 'Kernel-Dag'!
+
+!TDagSink methodsFor: 'accessing'!
 
 dagChildren
 	^ #()
@@ -181,6 +184,41 @@ dagChildren: aCollection
 	aCollection ifNotEmpty: [ self error: 'A DagSink cannot have children.' ]
 ! !
 
+Trait named: #TDerivedDagChildren
+	package: 'Kernel-Dag'!
+
+!TDerivedDagChildren methodsFor: 'accessing'!
+
+addDagChild: aDagNode
+	self error: 'Cannot add child for a TDerivedChildren.'
+!
+
+dagChildren
+	self subclassResponsibility
+!
+
+dagChildren: aCollection
+	self error: 'Cannot set children of a TDerivedChildren.'
+! !
+
+Trait named: #TSingleDagChild
+	package: 'Kernel-Dag'!
+
+!TSingleDagChild methodsFor: 'accessing'!
+
+dagChild
+	self subclassResponsibility
+!
+
+dagChildren
+	^ { self dagChild }
+! !
+
+TDagSink setTraitComposition: {TDerivedDagChildren} asTraitComposition!
+TSingleDagChild setTraitComposition: {TDerivedDagChildren} asTraitComposition!
+DagSink setTraitComposition: {TDagSink} asTraitComposition!
+! !
+
 !Object methodsFor: '*Kernel-Dag'!
 
 isDagNode