From: Xavier Noria Date: 2008-08-28T20:46:36+09:00 Subject: Re: how to avoid passing by reference and how to copy objects Perl is only pass-by-reference by the way, sometimes it helps to see a pass-by-reference example. So in Perl you can do this: sub some_function { $_[0] = 5 } my $a = 7; some_function($a); # now $a is 5 Perl has references, but the "reference" in "pass-by-reference" is a different word, it means the parameters of the function are *aliases* of the arguments in the caller.