Instead, package users should use the state_name_for subroutine to access it. This will help coders avoid this pitfall: 
if( $MyConfig::state_name_for{AL} = 'Alaska' ){
   print  "oops! we just assigned Alaska to the AL key!\n";
}

[download]

But your state_name_for is defined 

sub state_name_for{
  return \%state_name_for;
}

[download]
That returns a reference to the hash %state_name_for and exposes it to the user just like accessing the hash directly. To protect the hash, put something like this in MyConfig: 
sub get_state_name { $state_name_for{ +shift} }

[download]
and keep %state_name_for a private lexical in MyConfig. Now the user can't change the hash content, accidentally or deliberately. They still can query the hash the way it is intended.

Anno

In reply to Re^5: Variable declaration in 'required' file doesn't work under 'strict'? by Anno
in thread Variable declaration in 'required' file doesn't work under 'strict'? by punch_card_don

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