The offending line, as reported in your error, is %hash = ($tmp);. The left hand-side of that statement is a hash and the right-hand side is a list with one element $tmp. The issue you are having is that you are assembling a string and trying to assign that to the hash instead of just storing directly in the hash. You could get Perl to do what you are asking it to do with eval, but why do that when you could just assign the values in the first place? This smells of an XY Problem. 
while ( my ($key, $value) = each(%$po) ) {
    $hash{$key} = $value ? $value : "a";
}

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In reply to Re: Hash assignment "odd" ness by kennethk
in thread Hash assignment "odd" ness by phigment

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