Placeholder for documentation topics that lack

If a defxdoc form ends up having no parents, it ends up being put here. See also undocumented.

Historic note. We used to put these topics directly underneath top
instead. But we found that during development, this sometimes led to a
strange-looking hierarchy where ``random'' topics were presented as top-level
topics just because they were new or being moved around or because set-default-parents forms weren't quite in the right places. To avoid this,
we now move these topics to

- Find-a-base-case-translated-aux
- Find a base-case within a translated term.
- Find-a-base-case-aux
- Find a base-case within an untranslated term.
- Atc-exec-binary-strict-pure-rules
- Rules for executing strict pure binary operations.
- Find-a-base-case-translated
- Find a base-case within a translated term.
- Promotion-uaconversion-theorems
- Two theorems about integer promotions and usual arithmetic conversions.
- Defdefparse-table
- Table of
`defdefparse`calls. - Atc-exec-expr-call-rules
- Rules for
`exec-expr-call`. - Missing-parents-test
- A topic with no
:parents .