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in reply to (jeffa) 2Re: Trying to solve N-Queens
in thread Trying to solve N-Queens

Call me crazy, but whenever I need a deep copy, I use freezethaw... just to be sure, 'cause data structures have a tendency to grow beyond their original intentions...
#!/usr/bin/perl -w use strict; use Data::Dumper; use FreezeThaw qw/ thaw freeze /; my $ds = { -foo => [ -bar => [0, 1], 3 ], -ping => 1 }; $ds->{-zort} = \$ds; my ($dsft) = thaw freeze $ds; $dsft->{-ping} = 2; print Dumper [$ds, $dsft];
See... $ds and $dsft are two different objects now! yay. And no matter how they change, the deep copy will work for ever and ever.
[admin@ensim admin]$ perl ./test.pl $VAR1 = [ { '-zort' => \$VAR1->[0], '-ping' => 1, '-foo' => [ '-bar', [ 0, 1 ], 3 ] }, { '-ping' => 2, '-zort' => \$VAR1->[1], '-foo' => [ '-bar', [ '0', '1' ], '3' ] } ]; [admin@ensim admin]$