The answer is that only by running the program you can answer your question.

OK, but how can I answer this by running??? 

I'm calling different subs in list context. Some return a reference 
of an array, others return an array by list.

How can I distinguish both if the the array has only one element, 
a reference of an array?

Even calling both a second time in scalar context doesn't help.

In reply to Re^2: check for wantarray? by KurtZ
in thread check for wantarray? by KurtZ

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