A combination of scheme and as-index, with the
following special cases when a single datum is provided:
If datum is a quote form, then the quote is
removed from the key (so that it’s sorted using its unquoted
If datum is a string, then quotes are removed from the
key (so that it’s sorted using the string content).
as-index and defterm. The content normally should be
plural, rather than singular. Consider using deftech,
instead, which always indexes.
idefterm, but plural: adds an “s” on the end of the content
for the index entry. Consider using deftech, instead.
combination of file and as-index, but where the sort
key for the index iterm does not include quotes.
combination of envvar and as-index.