In fact, passing by reference is a must to preserve the values in separate data structures, even an array and scalar. For instance: 
my @array = qw ( 1 2 3 4 5 );
my $num = 6;

&testsub ( @array, $num );

sub testsub {
   my ( @list, $single ) = @_;
   print @list;
}

[download]
will print: 
123456

[download]
Passing those values via the @_ flattens all values into one long list. However: 
my @array = qw ( 1 2 3 4 5 );
my $num = 6;

&testsub ( \@array, $num );

sub testsub {
   my ( $list, $single ) = @_;
   print @$list;
}

[download]
will print: 
12345

[download]
where passing the array by ref will keep the values from all merging into the single list.

In reply to Re: Is it possible to do pass by reference in Perl? by bradcathey
in thread Is it possible to do pass by reference in Perl? by Anonymous Monk

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