[tomkaos]

Worst than 0 and 1 is to have the choice. In Visual Basic 6 you have the option between the base 0 or 1 for each module. It make debugging a nightmare and you can create bug just by copy/pasting code from one program to other with a different base index.

[GuB-42]

You also have the choice in Perl, because of course, it is Perl.

The old way of doing it was setting the $[ variable to 1. You can actually set it to any value, in case you prefer to start your arrays at 42. It is now deprecated but you now have Array::Base that offers similar functionality.

Use it if you absolutely hate the person who will read your code, as if having someone read Perl code wasn't hateful enough.

[hoosieree]

One of the least-loved APL features is the fact that you can change the index origin at runtime.