Leading on from jdporter & chas' answers:

1) because you may want to pass a scalar, a list and a hash to a subroutine. You can do that with: 

testfunc($scalar,\@array,\%hash);

sub testfunc
{
 my ($scalar,$arrayref,$hashref) = @_;
}

[download]

2) Because hash references are fundamental to OO perl.

3) (Elaborating chas a little) Because a data structure like:

my $appointments = {
                    monday=> { "10:30"=>"dentist",
                               "11:30"=>"doctor" },
                    tuesday => { "10:30" => " planning meeting",
                                 "16:30" => " funding deadline" }
                    };

[download]

can be very useful.

4) Because once you start using array refs and hash refs, you'lll wonder how you ever managed without them.

I may be missing something, but I rarely have occasion to use a scalar ref in the simple $ref = \$var; form.

Update:Struck out 'hash' in 'hash references' at blazars suggestion - TIMTOWTDI.

--------------------------------------------------------------

"If there is such a phenomenon as absolute evil, it consists in treating another human being as a thing."

John Brunner, "The Shockwave Rider".

In reply to Re: Why use references? by g0n
in thread Why use references? by w3b

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