Hi Monks, I've been confused today by the following phenomenon: 
script 1

foreach (qw/a b c d/){$hash{$_}++};
print keys %hash, "\n";
print keys %{$hash{'wrong'}};
print keys %hash, "\n";

OUTPUT:

cabd
cwrongabd

---------------------------------
script 2 

foreach (qw/a b c d/){$hash{$_}++};
print keys %hash, "\n";
print $hash{'wrong'};
print keys %hash, "\n";

OUTPUT:

cabd
cabd

[download]
why does the third line in the first script seemingly cause the key 'wrong' to magically appear in the hash, whereas the corresponding line in the second script doesn't? A brief reading of perlfunc:keys doesn't seem to give me an answer, so I guess there must be a deeper reason. Can anyone enlighten me?

In reply to puzzling behaviour of keys function by Anonymous Monk

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