private SNode searchInSuperTypes(SNode subType, CoercionMatcher superType, boolean isWeak) {
StructuralNodeSet<?> frontier = new StructuralNodeSet();
StructuralNodeSet<?> newFrontier = new StructuralNodeSet();
StructuralNodeSet<?> yetPassed = new StructuralNodeSet();
frontier.add(subType);
while (!frontier.isEmpty()) {
Set<SNode> yetPassedRaw = new THashSet<SNode>();
// collecting a set of frontier's ancestors
StructuralNodeSet<?> ancestors = new StructuralNodeSet();
for (SNode node : frontier) {
mySubTyping.collectImmediateSuperTypes(node, isWeak, ancestors, null);
yetPassedRaw.add(node);
}
ArrayList<SNode> ancestorsSorted;
ancestorsSorted = new ArrayList<SNode>(ancestors);
Collections.sort(
ancestorsSorted,
new Comparator<SNode>() {
public int compare(SNode o1, SNode o2) {
return TypesUtil.depth(o2) - TypesUtil.depth(o1);
}
});
List<SNode> results = new ArrayList<SNode>();
for (SNode ancestor : ancestorsSorted) {
if (superType.matchesWith(ancestor)) {
results.add(ancestor);
}
}
if (!results.isEmpty()) {
if (results.size() > 1) {
results = mySubTyping.eliminateSuperTypes(results);
}
if (!results.isEmpty()) {
return results.get(0);
}
}
for (SNode passedNodeRaw : yetPassedRaw) {
yetPassed.add(passedNodeRaw);
}
for (SNode passedNode : yetPassed) {
ancestors.removeStructurally(passedNode);
}
for (SNode ancestor : ancestors) {
Pair<Boolean, SNode> answer =
getCoerceCacheAnswer(ancestor, superType.getMatchingPattern(), isWeak);
if (answer != null) {
if (answer.o1 && answer.o2 == null) {
// System.out.println("coerce optimized");
continue;
}
}
newFrontier.addStructurally(ancestor);
yetPassed.addStructurally(ancestor);
}
frontier = newFrontier;
newFrontier = new StructuralNodeSet();
}
return null;
}
