Sorry,

Spoke too soon.

None of what you sggested works.

#! /usr/bin/perl
use strict;
use warnings;

sub p1 {
    my $n1;
    $n1=scalar(@_);
    if  (@_) {
        print "Has elements\n";    
    }
    
    print "1. Parameters to the sub p1 $n1\n";
    my $p1=shift;
    if  (@_) {
        print "Has elements\n";    
    }
    else {
        print "Has no elements\n";    
    }
    print "2. p1=$p1\n";
}
p1 $ARGV[0];

[download]
Try passing nothing to the script you will see it still states one argument.

In reply to Re^2: Question: Is undef a valid argument? by jujiro_eb
in thread Question: Is undef a valid argument? by jujiro_eb

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