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From: sjg@melb.bull.oz.au (Simon J. Gerraty)
Newsgroups: comp.mail.sendmail
Subject: LHS map lookup.  Missing feature in IDA sendmail?
Message-ID: <1991Jun3.090222.13897@melb.bull.oz.au>
Date: 3 Jun 91 09:02:22 GMT
Sender: news@melb.bull.oz.au (USENET News Account)
Organization: Bull HN Information Systems Australia.
Lines: 34
Nntp-Posting-Host: sun0

In the process of building/testing sendmail-5.65+IDA, I seem to
have come accross a need for a new feature.

The $(x key $@ arg $: default $) feature is _just_ what I have
always wanted on the RHS of a re-write rule.

However I am used to having Sun's $%x and $!x features for
checking a key in a map in the LHS of the rules.

Ie.  I want to be able to have a rule match iff a key is present
in a map, or iff a key is NOT present in a map.  Then I'd like
to be able to make use of the lookup feature.

This seems such a fundamental requirement - that obviously I'm
not thinking right.  Could some one please:
1/ mail me an example of how the current IDA features can be
   used to replace something like:

R$*<@$%Y>$*	$#ether $@$2 $:$1<@$2>$3	user@etherhost

2/ let me know whether someone else has already done this.
   
3/ set me straight :-)

Its been a busy few weeks, so please flame > /dev/null if I'm
obviously not thinking properly :-)

Thanks!

-- 
Simon J. Gerraty        <sjg@sun0.melb.bull.oz.au>      (work)
                        <sjg@zen.void.oz.au>            (home)

#include <disclaimer>   /* imagine something *very* witty here */