This stirs up some memories of Perl, where flattening arrays/lists is the default, and you need explicit references to have nested arrays or hash tables. I reme

This stirs up some memories of Perl, where flattening arrays/lists is the default, and you need explicit references to have nested arrays or hash tables. I remember it used to be a kind of foot-seeking gun for newbies, but I never ran into trouble with it once I understood references (which isn't super hard).