use strict;
use Data::Dumper;

my %lexicon = (
    foo => 'boink',
    bar => 'blink',
    baz => 'squirm',
);

sub
grop
{   
    my $lexlist = shift || [sort keys %lexicon];
    print Dumper($lexlist);
}
 
grop(['gump','snoop','grock']);
grop();