Re: XPath expression that yields the same result as x

I would normally use maps for grouping in XPath 3.1.

Maps are nice and compact for grouping, I agree, but in the end I find
that using them I can't conserve the original input order or control the
order of items at all as I am used to from XSLT 2 with normal grouping.

So in most cases the requirements are not only to group but also to
establish an order for the groups, sometimes the original input order,
sometimes based on sort keys, and with items in a map being essentially
without order I often find it at least inconvenient to first create a
map and later have to ensure I get the wanted order when outputting the map.