sub subParams {
  my %parameters = @{shift(@_)};
  my @ret = ();

  while (my ($entry,$default) = splice(@_,0,2)) {
    if(length $parameters{$entry}) {
      push(@ret,$parameters{$entry});
    }
    else {
      push(@ret,$default);
    }
  }

@ret;
}

sub sample { 
  my ($p0,$p1) = subParams(\@_,p0=>'d0',p1=>'d1');
}

#With the above code, each of these calls are indentical

sample(p0=>'d0',p1=>'d1');
sample(p1=>'d1',p0=>'d0');
sample(p0=>'d0');
sample(p1=>'d1');
sample();