diff --git a/src/plugins/texteditor/convenience.h b/src/plugins/texteditor/convenience.h
index e4f5f0480bc..f4302cd5f31 100644
--- a/src/plugins/texteditor/convenience.h
+++ b/src/plugins/texteditor/convenience.h
@@ -37,6 +37,7 @@ QT_END_NAMESPACE
 namespace TextEditor {
 namespace Convenience {
 
+// line is 1-based, column is 0-based
 TEXTEDITOR_EXPORT bool convertPosition(const QTextDocument *document,
                                        int pos,
                                        int *line, int *column);