My humble understanding is:
  1. Here you create the array, then set all it's values to nothing, therefore the array is defined, but has no content
  2. In this case you undefine the array, so it's not defined any more and also has no content. It still exists, so you can still use it without error.
  3. As other have said here you're simply setting the first value of the array to an undef value.

Interesting question.

In reply to Re: using undef on a array by ajt
in thread using undef on a array by Anarion

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