Yeah, I remember when I was trying to parse XML into some lua tables and it forever stumped me how to represent something like
<thing important_param=10 other_param="abracadabra"> stuff </thing>
You just have to have different ways to turn different tags into stuff in your program and that’s a huge amount of overhead to think about when all I want is a hash map and maybe an array.
Personally, I prefer duplicate keys to be eaten by the parser but I can see how it’d be beneficial to prevent them.