[bug #59290] ms: add register to enable backtraces on diagnostics

[Ingo Schwarze]

Follow-up Comment #3, bug #59290 (project groff):

Re comment #2: These are all fair points, so probably you are right that a
register makes sense here.

Another aspect to consider:  the task is generic, not specific to ms.  So
ideally, the naming would harmonize with the naming schemes of *all* macro
sets (or with the naming of roff core registers?) such that it can be used in
whatever macro set desires such functionality.


The problem that getting a message about a "diversion" is likely to look like
a diversion from hell to the user seems like a generic problem of languages
that do preprocessing.  If you abuse #defines or C++ templates creatively
enough, the compiler is likely to throw messages at you such that you ask
yourself, "what's this? i never wrote anything remotely similar to what the
compiler is complaining about!"

Often, the preprocessor will transform the input without being able to fully
check validity, and then a later stage of processing may end up emitting a
confusing error message.  Some issues of this kind can sometimes be caught by
doing preliminary validation in the preprocessor, but that shouldn't be
overdone because it can add excessive complexity and is prone to causing bugs.
 Apart from that, there is not much that can be done, short of designing a
coherent one-level language in the first place and refraining from code
autogeneration.


The graph seems confusing and ambigous to me: are the crossings common
crossings or switches?  I had to look at the manual page to figure out that
they are almost certainly intended as switches.  But then, why are there two
different tracks leading from AI to NH?  My impression is the following plain
text description would be smaller, less confusing, more accessible, and more
precise:

  [RP] [TL AU AI] [AB AE] [ [NH | SH] [[PP | LP] text]* ]*

In general, redundant use of drawings in documentation is evil.

    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?59290>

_______________________________________________
  Message sent via Savannah
  https://savannah.gnu.org/