Hmm, I think I own you now - this uses code that writes code:

[%# Run this through tpage - from Template %]

[% numbers = [ 1, 2, 3, 4, 5, 6 ] -%]
[%   end   = '\)' -%]
[%   start = '\w+\(' -%]


my %functions = ();

[% FOR level = numbers -%]
$functions{ [% level %] } = sub { 
  $_[0] =~ s/[% end %]{[% level %]}$//o;  
  $_[0] =~ s/^([% start %]){[% level %]}//o;
  return $_[0];
};
[% END -%]

sub get_proparg_evdb {
 $_ = $_[0];
 my $level  = $_[1] || return $_;

 if ($level == -1) {
   m/\(([^()]+)\)+/;
   return $1;
 } 

 return &{$functions{ $level }}( $_ ) 
   || die 'Add universal function here';
}
[download]

The complete code that is produced is here:

my %functions = ();

$functions{ 1 } = sub { 
  $_[0] =~ s/\){1}$//o;  
  $_[0] =~ s/^(\w+\(){1}//o;
  return $_[0];
};
$functions{ 2 } = sub { 
  $_[0] =~ s/\){2}$//o;  
  $_[0] =~ s/^(\w+\(){2}//o;
  return $_[0];
};
$functions{ 3 } = sub { 
  $_[0] =~ s/\){3}$//o;  
  $_[0] =~ s/^(\w+\(){3}//o;
  return $_[0];
};
$functions{ 4 } = sub { 
  $_[0] =~ s/\){4}$//o;  
  $_[0] =~ s/^(\w+\(){4}//o;
  return $_[0];
};
$functions{ 5 } = sub { 
  $_[0] =~ s/\){5}$//o;  
  $_[0] =~ s/^(\w+\(){5}//o;
  return $_[0];
};
$functions{ 6 } = sub { 
  $_[0] =~ s/\){6}$//o;  
  $_[0] =~ s/^(\w+\(){6}//o;
  return $_[0];
};

sub get_proparg_evdb {
 $_ = $_[0];
 my $level  = $_[1] || return $_;

 if ($level == -1) {
   m/\(([^()]+)\)+/;
   return $1;
 } 

 return &{$functions{ $level }}( $_ ) 
   || die 'Add universal function here';
}
[download]

             Rate       ori m-elegant     ori++      evdb
ori        6234/s        --      -36%      -40%      -51%
m-elegant  9690/s       55%        --       -7%      -24%
ori++     10373/s       66%        7%        --      -18%
evdb      12690/s      104%       31%       22%        --
[download]

Code that writes code - tip 29 from the pragmatic programmer.

--tidiness is the memory loss of environmental mnemonics