I was pretty sure you could declare a hash with use constant.. or well, a hash reference anyways: 
use constant HASH_REF => {
   constant_key => 'constant_value',
   ...
};

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Then use it like you would any hashref ie:
print HASH_REF->{constant_key}
or
foreach my $key (keys %{ &HASH_REF }) { ... }
or the even weirder:
foreach my $key (keys %{ HASH_REF() }) { ... }

In reply to Re^4: Using Constants in Perl by the_slycer
in thread Using Constants in Perl by qazwart

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