Any Perl 5 programmer who’s worked with Perl 5 more than a few months has learned about how invaluable the Data::Dumper module is. The ability to say
use Data::Dumper;
print Dumper( %hash );
is a godsend to debugging data structures of any complexity.
Perl 6 has this dumping built in.

uniqua:~/rakudo/lab $ cat dumper
#!/usr/local/bin/perl6
use v6;
my %hash = (
'this'     => 'that',
'year'     => 2112,
'matcher'  => regex { ^ M(r|rs|s). s+ (w+) s+ Wall $ },
'rational' => 0.5,
'num'      => (0.5).Num,
);
say %hash.perl;
# Or %hash.perl.say
uniqua:~/rakudo/lab $ ./dumper
{"num" => 0.5, "this" => "that", "year" => 2112,
"rational" => 1/2, "matcher" => { ... }}

Regex dumping does not display the actual regex yet, but Patrick Michaud says it’s coming soon.