Path: utzoo!attcan!uunet!fernwood!decwrl!ucbvax!tut.cis.ohio-state.edu!mailrus!usenet.ins.cwru.edu!cwjcc!ncoast!allbery
From: allbery@NCoast.ORG (Brandon S. Allbery)
Newsgroups: comp.lang.perl
Subject: Re: subroutine inspecting its calling environment
Message-ID: <1990Mar10.025904.25473@NCoast.ORG>
Date: 10 Mar 90 02:59:04 GMT
References: <JBW.90Mar5185907@bucsf.bu.edu> <7283@jpl-devvax.JPL.NASA.GOV> <100405@convex.convex.com>
Reply-To: allbery@ncoast.ORG (Brandon S. Allbery)
Followup-To: comp.lang.perl
Organization: North Coast Public Access UN*X, Cleveland, OH
Lines: 25

As quoted from <100405@convex.convex.com> by tchrist@convex.COM (Tom Christiansen):
+---------------
| In article <7283@jpl-devvax.JPL.NASA.GOV> lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall) writes:
| >In article <JBW.90Mar5185907@bucsf.bu.edu> jbw@bucsf.bu.edu (Joe Wells) writes:
| >: 1.  Can a subroutine tell whether it was invoked without arguments?
| >
| >Not that I know of.
| 
|     sub callme {
| 	local($count) = $#_ + 1;  # assumes $[ == 0
| 	printf "i was called with %s argument%s\n", 
| 		    $count, ($count == 1) ? '' : 's';
|     } 
+---------------

More portably,

	local($count) = $#_ - $[ + 1;

Just another Perl diver,						;-)
++Brandon
-- 
Brandon S. Allbery (human), allbery@NCoast.ORG (Inet), BALLBERY (MCI Mail)
ALLBERY (Delphi), uunet!cwjcc.cwru.edu!ncoast!allbery (UUCP), B.ALLBERY (GEnie)
BrandonA (A-Online) ("...and a partridge in a pear tree!" ;-)