use Data::Dumper;

sub foo {
    $_[0] = undef;
}

sub bar {};

my @a;

@a = ();
foo( $a[0] );

print Dumper \@a;

@a = ();
bar( $a[0] );

print Dumper \@a;

[download]
This prints: 
$VAR1 = [
          undef
        ];
$VAR1 = [];

[download]

As I read the paragraph you quoted, some earlier versions of perl would have produced identical output in both cases.

-guinex

In reply to Re: perlsub question.. by guinex
in thread perlsub question.. by Anonymous Monk

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