Re: Counting score program exit code and negation

dattier(_at_)wwa(_dot_)com (David W. Tamkin) writes:
> Well, ok, I've deconstructed it.  (You knew I would.)
To summarize for those trying to follow David's deconstruction,
into the 'calling' procmailrc, put:


# Put the regexp of the lines to examine in REGEXP
# Also count Apparently-To: headers, just because they're obnoxious.
:0
* ^Resent-(From|Date|To|Cc|Message-Id):
{ REGEXP = "^(Resent-(To|Cc)|Apparently-To):" }
:0E
{ REGEXP = "^((Apparently-)?To|Cc):" }


# Put the string to match against into $HEADERLINES
:0 # H is implicit
* $ ()\/$REGEXP(.*)$
{
  # Set up the initial run.
  HEADERLINES = $MATCH

  # What's the maximum number of items allowed?  This passes, one more
  # get's torched.
  EXCESS = -19

  # Let it rip.
  INCLUDERC = count_comma_sep.rc

 :0 # count was predefined and prejudiced at -19 
 * $ $EXCESS^0
 { EXITCODE=77 HOST }
}



And in the count_comma_sep.rc file:


# Goal: count the number of comma-separated items in $HEADERLINES in
# lines that begin with $REGEXP.  EXCESS will start at the negative of
# the maximum allowed, then count up towards zero.

# Clear MATCH, then count the items in the first match, if any.
MATCH=
:0
* 1^0 HEADERLINES ?? $ $REGEXP\/.*
* 1^1 MATCH ?? ,
{
    # Okay, increment EXCESS by $=.
    :0
    * $ $EXCESS^0
    * $ $=^0
    { EXCESS = $= }

    # Now, do we need to recurse?  Only if there's still another
    # match to $REGEXP.  If so, we reset $HEADERLINES to contain only
    # the second match and beyond, and then we take another ride.
    :0
    * HEADERLINES ?? $ $REGEXP(.*$)*\/$REGEXP(.*$)*
    {
        HEADERLINES = $MATCH

        # Recurse!
        INCLUDERC = $_
    }
}


The one optimization that I can still see is to add the following
condition to the recursion recipe:

    :0
    * EXCESS ?? ^[1-9]
    * HEADERLINES ?? $ $REGEXP(.*$)*\/$REGEXP(.*$)*
    {
        ...
    }

That'll avoid the recursion if we've already gone positive.  Note that
this is a Good Thing if just to avoid the copies that the very next
condition will cause in coping the matched text back and forth from
HEADERLINES to MATCH and back again.

HOWEVER...

With this added condition, it becomes more complicated if you want to
get the total count, with no upper limit criteria as is true in the
original goal.  If you think it unlikely that you'll need to do that,
or the extra bother of having to set EXCESS to negative 10 million
doesn't bother you, go ahead and add the condition.

Philip Guenther