Hello fellow monks,

testing is a great thing, especially if you find something like the following 

my @y;
print "Array is empty: ", 
   (0 == scalar @y ? "yes" : "no"), "\n";
print "first element: ", 
   ( $y[0] ? "defined" : "undefined"), "\n";
print "Array is empty: ", 
   (0 == scalar @y ? "yes" : "no"), "\n";
print "Type of first element: ",  
   ref \$y[0], "\n";
print "Array is empty: ",
   (0 == scalar @y ? "yes" : "no"), "\n";

[download]

You find that reading 0th element from an empty array gives undefined and leaves the array untouched. But using ref on that non-existing element creates it and returns scalar.

It took me an hour to find why my array was not empty. Could anybody explain this a bit? Somwhow, I feel like a beginner again.

And it came to pass that in time the Great God Om spake unto Brutha, the Chosen One: "Psst!"
(Terry Pratchett, Small Gods)

In reply to ref defines array element? by Brutha

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