in reply to Re^3: Hashing it out: defined? exists?
in thread Hashing it out: defined? exists?

Thanks for the info. The exists documentation does warn that your first example of autovivification ($h{$i}{$j}) will autovivify even if you're checking with exists. That is, 
{
   my %h;
   1 if exists $h{foo}{bar};
   print("exists 2:  ", (%h ? "auto-vivi" : "empty"), "\n");
}

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prints "auto-vivi".

But for some reason I thought it was easier to autovivify keys.

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Re^5: Hashing it out: defined? exists?
by ikegami (Patriarch) on Sep 02, 2005 at 20:25 UTC
    Keys are never auto-vivified. They are always created through assignment (incl the implicit assignment of an autovivified hash or array as shown in an earlier post). 
    $h{$k} = $v;
@h{$k} = ($v);
%h = ($k, $v);  # Also removes everything else.

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    .
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