Option to bypass storing types when opening model

src/ifcparse/IfcFile.cpp

@@ -651,6 +651,17 @@ IfcParse::filetype IfcParse::guess_file_type(const std::string& fn) {
     }
 }
 
+void IfcParse::InstanceStreamer::bypassTypes(const std::set<std::string>& type_names) {
+    for (auto& name : type_names) {
+        try {
+            types_to_bypass_.push_back(schema_->declaration_by_name(name));
+        } catch (const IfcException&) {
+            continue;
+        }
+    }
+ }
+
+
 std::optional<std::tuple<size_t, const IfcParse::declaration*, IfcEntityInstanceData>> IfcParse::InstanceStreamer::readInstance() {
     std::optional<std::tuple<size_t, const IfcParse::declaration*, IfcEntityInstanceData>> return_value;
 
@@ -698,6 +709,15 @@ std::optional<std::tuple<size_t, const IfcParse::declaration*, IfcEntityInstance
                 goto advance;
             }
 
+            for (auto& ty : types_to_bypass_) {
+                if (entity_type->is(*ty)) {
+                    bypassed_instances_.push_back(current_id);
+                    // Why is this a conditional clause in the loop?
+                    current_id = 0;
+                    goto advance;
+                }
+            }
+
             parse_context ps;
             lexer_->Next();
             try {