in reply to How To Print Single Element From Nested Hashes?

List::MapMulti?

use List::MapMulti qw(mapm);

my @keys = sort keys %hash;
mapm {
  my ($QB1, $QB2, $RB1, $RB2) = @_;
  ...;
} \@keys, \@keys, \@keys, \@keys;

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... or even...

use List::MapMulti qw(mapm);

my @keys = sort keys %hash;
mapm {
  my ($QB1, $QB2, $RB1, $RB2) = @_;
  ...;
} (\@keys) x 4;

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use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In Section Seekers of Perl Wisdom