I agree with Alf; it is a bug in Perl's pseudohash support. You happen to have an arrayref of which the first element is a hashref, and that is the definition of a pseudohash. This triggers the same all-you-can-eat memory bug:

my $foo;
$foo->[0]->{foo}->{bar} = 'baz';
$foo->{foo}->{foo}->{bar} = 'baz';

[download]

As ferrency points out, your examples are confusing. I suspect that something was lost when you trimmed them for posting. Even the first example, which (I think) you meant to be correct, fails on the data you posted. Either $foo needs an additional level of hashref (becoming HoHoH), or the foreach loop is not needed. Also, your return statements should be one level further out in all three examples.

I was working on an example of a less error-prone way to handle your AoHoH, when I realized that something was amiss in the example code. Can you clarify?

In reply to Re: Automagic Array to Hash Conversion? Pseudo-Hash Explosion by Util
in thread Automagic Array to Hash Conversion? Pseudo-Hash Explosion by tadman

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