print Dumper { %hash {qw{ a b c }} };
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In older Perls, you have to use a loop (or disguise it as map):

print Dumper { map { $_, $hash{$_} } qw( a b c ) };
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That "older Perls" method worked well for basic hashes. But what if I have a hash of arrays of hashes? Can I filter out the keys in the inner hash?

Hello MrSnrub,

If you want the output sorted as well as filtered, you can set $Data::Dumper::Sortkeys to do both together:

#! perl
use strict;
use warnings;
use Data::Dumper;

my %hash = (Fred => 'Wilma', Barney => 'Betty', Homer => 'Marge');

$Data::Dumper::Sortkeys = sub { [ sort grep { /^Fred|Barney$/ } keys %
+{$_[0]} ] };

print Dumper \%hash;
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Output:

23:01 >perl 1116_SoPW.pl
$VAR1 = {
          'Barney' => 'Betty',
          'Fred' => 'Wilma'
        };

23:01 >
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(See “sorting and filtering hash keys” in Data::Dumper#EXAMPLES.) Otherwise, choroba’s approach is clearly superior.

Hope that helps,

RoShamBoDump( \%myhash );
sub RoShamBoDump {
    my $orig = shift;
    my @keys = qw/ ro sham bo /;
    my %new;
    @new{ @keys } = @{ $orig }{ @keys };
    use Data::Dumper;
    print Data::Dumper->new([\%new])->Useqq(1)->Dump, "\n";
}
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