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Tied/Magical Array/Hash Elements Do Not Autovivify
For normal arrays $foo = \$bar[1] will assign undef to $bar[1] (assumi
+ng that it didn't exist before), but for tied/magical arrays and hash
+es such autovivification does not happen because there is currently n
+o way to catch the reference creation. The same problem affects slici
+ng over non-existent indices/keys of a tied/magical array/hash.