simplify dup check

diff --git a/modules/lmdbbackend/lmdbbackend.cc b/modules/lmdbbackend/lmdbbackend.cc
index 6cc027a42ed7224fd5d31f73c5b8b623fc0651af..ec425cc187ab7fc15937a8caa252935ceb5d6847 100644 (file)
--- a/modules/lmdbbackend/lmdbbackend.cc
+++ b/modules/lmdbbackend/lmdbbackend.cc
@@ -1672,12 +1672,9 @@ void LMDBBackend::getAllDomainsFiltered(vector<DomainInfo>* domains, const std::
       di.id = iter.getID();
       di.backend = this;
 
-      if (zonemap.count(di.zone) == 1) {
+      if (!zonemap.insert(std::make_pair(di.zone, di)).second) {
         dups.insert(di.zone);
       }
-      else {
-        zonemap[di.zone] = di;
-      }
     }
 
     for (const auto& zone : dups) {