Re: groff: grops and grodvi crash on invalid input

[John Gardner]

>
> What do you think about a warning for drawing outside the page boundaries?


I can't see that benefiting anybody, quite frankly. Since all coordinates
are precomputed, users are unlikely to see such a message in practice.

Personally, I find Groff's postprocessors too chatty, and would really
appreciate having the ability to silence certain warnings. Perhaps
something like:

x warn -unknown-x-cmd +out-of-bounds


… which would enable your proposed warning addition, and disable this
sodding message I'm sick of seeing:

grotty:<standard input>:15: error: X command without 'tty:' tag ignored


(For reference, it's complaining about the \X'meta: …' directives I
embedded in a few macros)



On Mon, 23 Nov 2020 at 02:46, G. Branden Robinson <
g.branden.robinson@gmail.com> wrote:

> At 2020-11-23T00:10:15+1100, John Gardner wrote:
> > IMHO, it would be more intuitive to make this
> [a positioning command before the first 'p' command]
> > a no-op, rather than an error (a warning at *most*). Users may wish to
> > "prepostprocess" the formatted output to control page order, extract
> > or inject existing pages from an earlier formatting run (etc)… things
> > that elevate the risk of an errant motion command appearing before the
> > first p command.
>
> Fair point.  Yes.  I'd like to see a warning for it, but nothing more
> drastic.
>
> > Roff.js, being designed to accommodate a range of troff
> > implementations and perform unattended document formatting, is
> > deliberately tolerant of input it doesn't expect (to a fault: I
> > actually need to make it a little stricter with error reporting...
> > I'll get back to that in 2021 probably…)
>
> Everybody's liberal in what they accept until the QAnon trolls and other
> defectors from the social contract show up, then they remember that
> norms are there for a reason.  ;-)
>
> What do you think about a warning for drawing outside the page
> boundaries?  N.B. I don't know how to actually implement such a thing
> yet.
>
> Thanks for the feedback!
>
> Regards,
> Branden
>