Since you bring up the subject of special variables, we should point out that your case 3 is essentially the same as case 1, but uses $, instead of $". 
do{ local $, = $"; say "5:", %hash;}

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Bill

In reply to Re^2: Print the contents of a hash without looping. by BillKSmith
in thread Print the contents of a hash without looping. by Anonymous Monk

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