in reply to Re^3: Using Constants in Perl
in thread Using Constants in Perl

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() }) { ... }

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Re^5: Using Constants in Perl
by jhourcle (Prior) on Mar 01, 2006 at 14:22 UTC

    You can declare it, yes, but it's not read only. The reference itself remains constant, but the data that it's referring to can be changed:

    use constant HASH_REF => { key => 'value' };
HASH_REF->{new_key} = 'new value';
HASH_REF->{key} = 'modified';
use Data::Dumper;
print Dumper HASH_REF;

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[d/l]

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