Another way to do this is with a separate %DEFAULTS hash that gets mixed in with the arguments passed. 

use Data::Dumper;

my %DEFAULTS = ( a => 'a default',
                 b => 'b default',
                 c => 'c default', );
my %args = ( a => 'a arg',
             b => undef, );
%args = ( %DEFAULTS, %args );

print Dumper \%args;
__END__
$VAR1 = {
          'c' => 'c default',
          'a' => 'a arg',
          'b' => undef
        };

[download]

Notice that this method keeps a value that exists but is not defined, so somebody can explicitly pass in undef if they want to. This may or may not be what you want.

In reply to Re^3: Simple Query on Operators by kyle
in thread Simple Query on Operators by Ewok_Wrangler

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