Re: A suggestion to add to gnu ed: command line option to start on line foo or bar.

[Antonio Diaz Diaz]

John Cowan wrote:
> > In addition I have also implemented
> > +?pattern to set the current line to the *last* line matching the pattern.
>
> Good feature; it is also present in 'ex'.

I took the idea from GNU nano. I have never used 'ex' and all the 
information I have about 'ex' comes from its POSIX page, which does not seem 
to mention +n, +/pattern, or +?pattern.

> > But I would like to know what do you think it should be the behavior when
> > there is no match for 'pattern'. I have made ed to immediately exit with
> > error status 1, but I can change that behavior if something better (and
> > not misleading) is suggested.
>
> I think you should in that case print "?" and go on, as it is mostly just a
> convenience, and the intention to edit the file is clear.  This is
> equivalent to what 'ex' does.
>
> However, this behavior is not so good in a script.  I think therefore you
> should add a command-line option -e (long form: --errexit), like the shell
> option, which causes termination with error status 1 when *any* error is
> detected.

I agree that ed should perhaps behave differently in the interactive and 
scripted cases, but I think we can use the existing option '-l, 
--loose-exit-status' to ignore a mismatch in the interactive case instead of 
using a new option to force an error in the scripted case.

I have just uploaded ed-1.20-pre1 with these changes implemented. Please 
test it and tell me what do you think.
http://download-mirror.savannah.gnu.org/releases/ed/ed-1.20-pre1.tar.lz

Best regards,
Antonio.