Passing References

A subroutine can receive a reference and read the data it points to.

pass_refs.pl

use strict;
use warnings;

sub total_points {
    my ($values_ref, $bonus) = @_;
    my $total = $values_ref->[0] + $values_ref->[1] + $values_ref->[2];
    $total = $total + $bonus;
    return $total;
}

my $bonus = ;
my $values_ref = [2, 4, 6];
my $total = total_points($values_ref, $bonus);

print "bonus=$bonus\n";
print "total=$total\n";

use strict;
use warnings;

sub total_points {
    my ($values_ref, $bonus) = @_;
    my $total = $values_ref->[0] + $values_ref->[1] + $values_ref->[2];
    $total = $total + $bonus;
    return $total;
}

my $bonus = ;
my $values_ref = [2, 4, 6];
my $total = total_points($values_ref, $bonus);

print "bonus=$bonus\n";
print "total=$total\n";

use strict;
use warnings;

sub total_points {
    my ($values_ref, $bonus) = @_;
    my $total = $values_ref->[0] + $values_ref->[1] + $values_ref->[2];
    $total = $total + $bonus;
    return $total;
}

my $bonus = ;
my $values_ref = [2, 4, 6];
my $total = total_points($values_ref, $bonus);

print "bonus=$bonus\n";
print "total=$total\n";

reference argument A reference argument lets a subroutine work with a shared data structure.