in reply to do $n exist in grep?

the parens in this statement might be moot

Do you mean that the () in (A|B) is kinda bad because it captures A or B as well as acting to place a limit around A|B? If so you can (?:A|B) instead which groups A|B, but doesn't capture the match.

If you mean something else, perhaps you would like to spell it out for us?

Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

In Section Seekers of Perl Wisdom