My perl (AS 5.61 on Windows XP) also dies, but not every time. Using diagnostics, I get the following message, among others:

Attempt to free unreferenced scalar at scratchpad2.pl line 5 (#2):
(W internal) Perl went to decrement the reference count of a scalar to
see if it would go to 0, and discovered that it had already gone to 0
earlier, and should have been freed, and in fact, probably was freed.
This could indicate that SvREFCNT_dec() was called too many times, or
that SvREFCNT_inc() was called too few times, or that the SV was
mortalized when it shouldn't have been, or that memory has been
corrupted.

[download]

which may help some, but I'm afraid is a little over my head.

Concerning the third antirice loop:

foreach my $key ( @{[%hash]} ) {
  # print "$key: @{[%hash]}\n";
  delete $hash{$key};
}

[download]
I thought it looked to be (conceptually) equivalent to something like:

foreach my $key (my @ary = %hash) {
  # print "$key: @ary\n";
  delete $hash{$key};
}

[download]

(which also 'works', BTW), but apparently it isn't the same, since uncommenting the print lines shows that the anonymous array reference (vocab a bit shaky here...) [%hash] shrinks by two items with each iteration, while the 'straight' array @ary remains unchanged.

Oh dear, not sure if all that helps at all...

dave

In reply to Re: Re: Re: Hashes: Deleting elements while iterating - deleting phantoms? by Not_a_Number
in thread Hashes: Deleting elements while iterating by knexus

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