Let me try and summarize what you have said so I can respond better:

• Until when used properly should not contain a negation.
• You implicitly seem to agree that negations in complex expressions do complicate programs.

Of course until simplifies things when used properly which is why I said :

However I believe that the use of until and unless and the likes are dangerous for precisely this reason. I find it far better to use while( ! ) and if(!) for complex conditions.

The problem is that one might start with:

until( eof ) {
[download]

until( eof or $found_all_elements_i_was_looking_for ) {
[download]

until( $no_error_opening_file or 
     ( eof and $need_not_process_beyond_eof )
     or $found_all_elements_i_was_looking_for ) {
[download]

Of course when each of $no_error_opening_file ... are themselves expressions its not simple anymore.

It is for exactly the same reason that I believe its good to have a ',' after the last element of a hash or to always ensure that ifs have blocks even if whats in the if is a single statement.

I will ignore the first and last chunks as they have little to do with my original thesis.

Given this I dont see where the disagreement lies? Did I miss something?