diff --git a/Source/NSDocumentController.m b/Source/NSDocumentController.m
index fe7a1a62f..79293abb6 100644
--- a/Source/NSDocumentController.m
+++ b/Source/NSDocumentController.m
@@ -549,6 +549,9 @@ static NSDictionary *TypeInfoForName(NSArray *types, NSString *typeName)
     return _recentDocuments;
 }
 
+@end
+
+@implementation NSDocumentController (Private)
 static NSString *NSEditorRole = @"Editor";
 static NSString *NSViewerRole = @"Viewer";
 static NSString *NSNoRole     = @"None";