Hi,

your @b array is not empty, it has one element which happens to be undef. If you run something like: 

print scalar @b;

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it will print 1, which is why, if you evaluate the array in boolean context (... if (@b);) you get a true value and your sentence is printed.

If you want to check if the array contains at least one defined element, yes, you probably have to do ... if grep { defined($_) } @b; or something similar. You may want something else, though, if your array is large.

Update: corrected a typo.

In reply to Re: How to determine if an array contains an undef value? by Laurent_R
in thread How to determine if an array contains an undef value? by thanos1983

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