Most efficient recipe [was: syntax enhancement dreams]

terry jones <terry(_at_)chiliad(_dot_)teclata(_dot_)es> wrote:
> David W Tamkin <dattier(_at_)wwa(_dot_)com> writes:
> > My sole argument for advocating the latter form is to save
> > forking perl when you're already running procmail.
> OK, I'm with you all the way on this. If you can avoid forking
> processes I think that's great...

Which gets into something I've been wondering:  suppose one is on three
mailing lists which procmail will sort to a special file.  My
understanding of what's been said is that it's faster for procmail to do
this internally, i.e.:

:0:
* (\
    ^From:.*first_mailing_list|\
    ^Sender:.*second_mailing_list|\
    ^Resent-From:.*third_mailing_list\
   )
mailinglist_folder

is faster than:

:0:
* ? egrep -s -f $HOME/.procmail/file_of_mailinglist_regexps
mailinglist_folder

Am I right that the first recipe would be faster than the second?  And
if so, at roughly what point would the second recipe become faster-- in
other words, if one is on 50 mailing lists instead of three, would the
first recipe still be faster?