You can use undef as the default value. See undef and defined.
my %defaults = ( bootpw => undef );

# is bootpw set to default?
if (defined $defaults{bootpw})
{
    print "Yes!\n";
}
else
{
    print "No.\n";
}

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In reply to Re: Default Values in Subroutines by repellent
in thread Default Values in Subroutines by walkingthecow

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