Yet, it's perfectly fine for an array to contain some values of undef. Why shouldn't I be allowed to print them?

Because you cannot "print undef"!

Without the warning, there is no way to distinguish between print ''; and print undef;.

Which may be fine in some contexts, but can be strongly indicative of a serious error in others.

Hence the warning is optional and turn on and off able. You can choose to turn it off in individual blocks of code, or if you feel it never benefits you, turn it off at the top of the module: use warnings; no warnings 'uninitialized';

It's a shame there isn't a better syntax for enabling everything except one or two categories.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Annoying 'Use of uninitialized value in concatenation' warning by BrowserUk
in thread Annoying 'Use of uninitialized value in concatenation' warning by alain_desilets

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