On Sun, Nov 06, 2022 at 06:38:24AM +0000, Werner LEMBERG wrote:
> If this is not possible, please make `texinfo.tex` suppress index
> entries that consist of whitespace only – perhaps together with a
> warning (or even an error). I also suggest to add some words to the
> manual about this case.
I added the following text:
+When using these options, it is possible to get an index entry with
+an empty sort key. To avoid this, specify a @code{@@sortas} directive
+in the index entry. For example:
+
+@example
+@@set txiindexbackslashignore
+@@findex @@sortas@{\@} \
+@end example
