Loop in AS macro

Hello Ping,

> If we want to write a script to expand the AS MACRO, how can we avoid to go
> into a loop if multiple AS-MACROs reference each other ?

I am not sure about your goals but just so you are aware you can
query our server (whois.radb.net) and issue the '!i' (ie, set expansion)
command.  Our server has all the big registries and many others (ie, 
ripe, radb, mci/cw, bell, apnic, verio, ...).  It's syntax is like this:

!i<set name>[,1]

The optional ',1' is a flag to turn on recursive look up.
Here is an example:

% whois -h whois.radb.net \!ias-onecall
A203
AS-IEI AS-INDNET AS-INDYNET AS-IONENET AS10403 AS10680 
AS10694 AS10718 AS11069 AS11106 AS11114 AS11126 AS11550 
AS12074 AS12277 AS13394 AS1767 AS5072 AS5689 AS6164 
AS6402 AS6571 AS7206 AS7900 AS8169 AS87

% whois -h whois.radb.net \!ias-onecall,1
A270
AS10403 AS10680 AS10694 AS10718 AS10893 AS11069 AS11106 
AS11114 AS11126 AS11550 AS11782 AS12074 AS12277 AS12314 
AS13394 AS13592 AS13921 AS14100 AS15116 AS17239 AS1767 
AS2711 AS2939 AS3060 AS5072 AS5689 AS6164 AS6365 AS6402 
AS6571 AS7206 AS7393 AS7900 AS8169 AS8175 AS87

I hope this helps.

--jerry