warning messages and correct output

[Patrice Dumas]

Hello,

There are more warnings now in texi2any, and some are for constructs
that may be correct for some output formats, but not all.  For an
example, a @table without @item is warned against, although it allows to
have an indentation that is consistent with indentation in other @table
in most formats, and it is the only way to get that indentation.
However, in Docbook, the result is invalid, and a quick look in yelp
shows that it is not indented here.  Other recent examples are @content
location when processed by @TeX (it was dropped afterwards), @*ref on 
@def line that should look good in HTML and Docbook, but not in Info 
or ps/pdf (also dropped now).

There are already possibilities to turn of pointer validation with
--novalidate, silence all warnings, with --no-warn.

When a warning deals with a dubious construct, but a construct that
nevertheless could lead to correct output in some format, we could want 
to do something smart, like warn only if the format output is one in
which the output looks bad.  Some warnings also do not lead to wrong
output in any output format (for example @-commands that do not appear
at line beginning, Printindex before document beginning and some
others).

I know that Karl does not like different levels of warning, such as a
pedantic level or an output of warnings only when processing a given
output format.  Yet, since these warnings are annoying some users, I
wanted to open the discussion here.  It may be closed rapidly, though...

Should we have different levels of warnings, maybe per format, or, more
simply a pedantic level, and only at this level, would construct that 
lead to correct output, or to correct output in some format would be
output?

-- 
Pat