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Author FAQ 4.73 How do I print out or copy a recursive data structure?
PerlFAQ Server

2005-07-29, 5:03 pm

This message is one of several periodic postings to comp.lang.perl.misc
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4.73: How do I print out or copy a recursive data structure?

The Data::Dumper module on CPAN (or the 5.005 release of Perl) is great
for printing out data structures. The Storable module on CPAN (or the
5.8 release of Perl), provides a function called "dclone" that
recursively copies its argument.

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

Where $r1 can be a reference to any kind of data structure you'd like.
It will be deeply copied. Because "dclone" takes and returns references,
you'd have to add extra punctuation if you had a hash of arrays that you
wanted to copy.

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



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