traverse() as a global function rather than method on IfcFile

src/ifcparse/IfcFile.h

@@ -55,7 +55,6 @@ private:
 	IfcSpfHeader _header;
 
 	void setDefaultHeaderValues();
-	void traverse(IfcUtil::IfcBaseClass*, std::set<IfcUtil::IfcBaseClass*>& visited, IfcEntityList::ptr list, int level, int max_level);
 	void register_inverse(unsigned, Token);
 public:
 	IfcParse::IfcSpfLexer* tokens;

src/ifcparse/IfcParse.cpp

@@ -1261,7 +1261,7 @@ bool IfcFile::Init(IfcParse::IfcSpfStream* s) {
 	return true;
 }
 
-void IfcFile::traverse(IfcUtil::IfcBaseClass* instance, std::set<IfcUtil::IfcBaseClass*>& visited, IfcEntityList::ptr list, int level, int max_level) {
+void traverse_(IfcUtil::IfcBaseClass* instance, std::set<IfcUtil::IfcBaseClass*>& visited, IfcEntityList::ptr list, int level, int max_level) {
 	if (visited.find(instance) != visited.end()) {
 		return;
 	}
@@ -1274,30 +1274,35 @@ void IfcFile::traverse(IfcUtil::IfcBaseClass* instance, std::set<IfcUtil::IfcBas
 		Argument* arg = instance->getArgument(i);
 
 		if (arg->type() == IfcUtil::Argument_ENTITY_INSTANCE) {
-			traverse(*arg, visited, list, level + 1, max_level);
+			traverse_(*arg, visited, list, level + 1, max_level);
 		} else if (arg->type() == IfcUtil::Argument_AGGREGATE_OF_ENTITY_INSTANCE) {
 			IfcEntityList::ptr entity_list_attribute = *arg;
 			for (IfcEntityList::it it = entity_list_attribute->begin(); it != entity_list_attribute->end(); ++it) {
-				traverse(*it, visited, list, level + 1, max_level);
+				traverse_(*it, visited, list, level + 1, max_level);
 			}
 		} else if (arg->type() == IfcUtil::Argument_AGGREGATE_OF_AGGREGATE_OF_ENTITY_INSTANCE) {
 			IfcEntityListList::ptr entity_list_attribute = *arg;
 			for (IfcEntityListList::outer_it it = entity_list_attribute->begin(); it != entity_list_attribute->end(); ++it) {
 				for (IfcEntityListList::inner_it jt = it->begin(); jt != it->end(); ++jt) {
-					traverse(*jt, visited, list, level + 1, max_level);
+					traverse_(*jt, visited, list, level + 1, max_level);
 				}
 			}
 		}
 	}
 }
 
-IfcEntityList::ptr IfcFile::traverse(IfcUtil::IfcBaseClass* instance, int max_level) {
+IfcEntityList::ptr IfcParse::traverse(IfcUtil::IfcBaseClass* instance, int max_level) {
 	std::set<IfcUtil::IfcBaseClass*> visited;
 	IfcEntityList::ptr return_value(new IfcEntityList);
-	traverse(instance, visited, return_value, 0, max_level);
+	traverse_(instance, visited, return_value, 0, max_level);
 	return return_value;
 }
 
+/// @note: for backwards compatibility
+IfcEntityList::ptr IfcFile::traverse(IfcUtil::IfcBaseClass* instance, int max_level) {
+	return IfcParse::traverse(instance, max_level);
+}
+
 void IfcFile::addEntities(IfcEntityList::ptr es) {
 	for( IfcEntityList::it i = es->begin(); i != es->end(); ++ i ) {
 		addEntity(*i);

src/ifcparse/IfcParse.h

@@ -257,6 +257,8 @@ namespace IfcParse {
 	};
 	
 	IfcEntityInstanceData* read(unsigned int i, IfcFile* t, boost::optional<unsigned> offset = boost::none);
+
+	IfcEntityList::ptr traverse(IfcUtil::IfcBaseClass* instance, int max_level = -1);
 }
 
 IFC_PARSE_API std::ostream& operator<< (std::ostream& os, const IfcParse::IfcFile& f);