Just a guess, I'm too tired ATM. ..

Your substr code might return an empty list in list context, which would mean passing am odd number of arguments to textfield

edit

Another guess: substr can also return an lvalue which is passed by reference to the @_ aliases, thus causing a different (ie broken) error handling.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re: "uninitialized value in subroutine exit" warning from CGI.pm by LanX
in thread "uninitialized value in subroutine exit" warning from CGI.pm by dwmcewan

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