11.12.1. Problem

11.12.2. Solution

use Storable;

$r2 = dclone($r1);

11.12.3. Discussion

@original = ( \@a, \@b, \@c );
@surface = @original;

@deep = map { [ @$_ ] } @original;

If @a, @b, and @c themselves contain references, the preceding map is no longer adequate. Writing your own code to deep-copy structures is laborious and rapidly becomes tiresome.

The Storable module provides a function called dclone that recursively copies its argument:

use Storable qw(dclone);
$r2 = dclone($r1);

Because dclone takes and returns references, you must add extra punctuation if you have a hash or arrays to copy:

%newhash = %{ dclone(\%oldhash) };