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

[Antonio Diaz Diaz]

Matthew Polk wrote:
> I like ed. I think it's a cool editor. One thing that in my opinion to
> make it more usable with other programs would be to have implemented,
> is a command line option to have ed automatically start at the
> specified line rather than at the very bottom.

John Cowan wrote:
> I would suggest doing this in an `ex`-compatible way.  That is, the command
> line argument +n causes the current line to be n, and the command line
> argument +/pattern causes the current line to be the first line matching
> the pattern.

I have already implemented that. In addition I have also implemented 
+?pattern to set the current line to the *last* line matching the pattern. 
It took some time because I needed to modify some regular-expression parsing 
functions of ed that required the input to end in a newline. I am now 
writing some tests because testing command-line options does not fit in the 
current testsuite of ed.

When 'n' is beyond the last line, I have made ed to remain at the last line. 
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.

Best regards,
Antonio.