I was checking the "Branches and Decisions" wiki entry at
https://wiki.contextgarden.net/System_Macros/Branches_and_Decisions, and I
saw that ConTeXt has a useful \doifalldefinedelse macro that checks a
comma-separated list of macro names and proceeds according to whether or
not all of the macros with those names are defined. I was curious as to
whether or not there is also a \doifanydefinedelse (or, equivalently, a
\doifallundefinedelse) macro that would check if *any *of the macros with
names in the comma-separated list is defined (or, equivalently, if all of
them are undefined). I don't see any mention of such a macro on the wiki
page, so I wanted to ask: has something like this already been implemented,
and if not, is there a simple way to do a check like this? This
functionality would be useful for performing some checks on a key-value
assignment, and passing a comma-separated list to a macro would be much
cleaner than doing a bunch of nested if-else blocks.

Joey