From: "trans.  (T. Onoma)" <transami@...>
Date: 2004-09-23T04:43:41+09:00
Subject: Re: Regexp Arity

On Wednesday 22 September 2004 03:15 pm, Warren Brown wrote:
> T.,
>
> > Just ran into a need to know how many parenthetical
> > groupings a Regexp has. Would #arity for Regexp be
> > a good idea?
>
>     Just to state the obvious, re.source.count('(') would work if you
> can guarantee there are no literal left parenthesis ("\(") in the
> regular expression.  If you can't guarantee that, you could always count
> them and subtract from the total, but that would be messy.

And /[(]/ too. More yuk. 

>     Perhaps we could use Regexp#length to mirror MatchData#length.

At first I didn't like, but actually that could work, okay.

T.