diff --git a/json2table.cc b/json2table.cc
index f63c8196599c9631a5d746085f842f8a025aecc1..65f3c230811fd88c05c6085327a3fc43d680a148 100644
--- a/json2table.cc
+++ b/json2table.cc
@@ -97,6 +97,7 @@ int main(int argc, char **argv) {
                 }
             }
             else if(item.is_array()) {
+                // It's an array of array. Print the matrix out!
                 for(auto &[_, value] : item.items()) {
                     rows[curr_row_pos].push_back(json_to_string(value));
                 }