Re: [PATCH v5 5/7] builtin/grep.c: add '--column' option to 'git-grep(1)'

René Scharfe [off-list ref] writes:

Am 10.05.2018 um 02:04 schrieb Junio C Hamano:
...

quoted

     $ git grep -v second
     $ git grep --not -e second

may hit all lines in this message (except for the obvious two
lines), but we cannot say which column we found a hit.  I am
wondering if it is too grave a sin to report "the whole line is what
satisfied the criteria given" and say the match lies at column #1.

And if we are planning to use this to implement '-o', then I'd
suggest that we'd say the matched part of the line is the whole
thing (i.e. so is column #1, eo is at the eol).

quoted

By doing so, obviously we can sidestep the whole "this mode is
sometimes incompatible" and "I need to compute a lot to see if the
given expression is compatible or not" issues.

FWIW, Silver Searcher 2.1.0 does just that:

	$ echo a | ag --column -v b
	1:a

ripgrep 0.8.1 as well:

	$ echo a | rg --column -v b
	1:1:a

Thanks for additional datapoints.