No doxygen for BoundingBox::NeighborType enumerator

[davydden]

subj.

[kronbichler]

Uncritical, postponing for the 9.2 release.

[bangerth]

As reported by @peterrum over at #9486:

The following enum classes seem to make also problems: Storage, ComponentExtractor and SIMDComparison...

[bangerth]

I've tried to figure out what's going on here several times but can't seem to make progress. There is no error in doxygen.log, and no other indication of what's going wrong. I've also tried to replace the enum class by enum or class to see whether doxygen likes that better, but the answer is no for enum. For class, it seems to work, but that's of course not useful. I'm not sure what we should do.

[tjhei]

I changed the settings

--- a/doc/doxygen/options.dox.in
+++ b/doc/doxygen/options.dox.in
@@ -39,12 +39,12 @@ BUILTIN_STL_SUPPORT    = YES
 # Build related configuration options
 #---------------------------------------------------------------------------
 
-EXTRACT_ALL            = NO
+EXTRACT_ALL            = YES
 EXTRACT_PRIVATE        = YES
 EXTRACT_STATIC         = YES
 EXTRACT_LOCAL_CLASSES  = YES
-HIDE_UNDOC_MEMBERS     = YES
-HIDE_UNDOC_CLASSES     = YES
+HIDE_UNDOC_MEMBERS     = NO
+HIDE_UNDOC_CLASSES     = NO
 SORT_MEMBER_DOCS       = NO

and now it shows up for me. I am not sure which of those settings did it, though. Worth changing the defaults for?

[bangerth]

Which of these settings is it?

[tjhei]

I played with this some more (including other extract_* flags we don't have in our options, setting @file, settings @relates, etc.): The only thing that makes this enum show up is EXTRACT_ALL=YES or putting it into a namespace (*).
*: we delete the "namespace dealii{" for doxygen, which makes this enum a global symbol. A workaround would be to move it into a namespace (or class scope).
Or, we could just enable EXTRACT_ALL?