I mostly use Tie::Hash::Vivify to prevent autovivification thus: 
  my $hashref = Tie::Hash::Vivify->new(
    sub { confess("No auto-vivifying!\n".Dumper(\@_)) }
  )

[download]
to avoid those annoyingly hard-to-track-down bugs where you've typoed a hash key.

In reply to Re^5: initialize all values in a hash by DrHyde
in thread initialize all values in a hash by AWallBuilder

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