Add comment for document::DocumentTypeRepoFactory::make method.

1 files changed, 4 insertions, 0 deletions

diff --git a/document/src/vespa/document/repo/document_type_repo_factory.h b/document/src/vespa/document/repo/document_type_repo_factory.h
index 0c8eecb035d..e104fe1f6a0 100644
--- a/document/src/vespa/document/repo/document_type_repo_factory.h
+++ b/document/src/vespa/document/repo/document_type_repo_factory.h
@@ -39,6 +39,10 @@ class DocumentTypeRepoFactory {
 
     static void deleteRepo(DocumentTypeRepo *repoRawPtr) noexcept;
 public:
+    /*
+     * Since same instance is returned for equal config, we return a shared
+     * pointer to a const repo.  The repo should be considered immutable.
+     */
     static std::shared_ptr<const DocumentTypeRepo> make(const DocumenttypesConfig &config);
 };