I am having some problems with tie and DBI. I have boiled the problem down to this short example. Basically, when you run the code below, you get the following error:

Can't use an undefined value as an ARRAY reference at ./example.pl lin
+e 37.
[download]

But if you comment out the line

$hash{blah} = 1;
[download]

Everything works as expected. FETCH returns an anonymous array and foreach properly iterates through it printing out the following:

$user = {
          'val' => 1
        };
[download]

Can anyone explain why when you tie a hash, then tie another inside a FETCH call, you see these problems? thanks very much, --eric

#!/usr/bin/perl -w
package MyTie1;
 
sub TIEHASH { bless {}, shift; }
 
sub STORE {
  my $self = shift;
 
  my ($key, $value) = @_;
 
  $self->{$key} = $value;
}
 
package MyTie2;
 
sub TIEHASH { bless {}, shift; }
 
 
sub FETCH {
 
  my $self = shift;
  my $key = shift;
 
  my %hash;
  tie %hash, 'MyTie1';
 
  $hash{blah} = 1;
 
 return [{val => 1}];
}
 
package main;
 
my %hash;
tie %hash, 'MyTie2';
use Data::Dumper;
foreach my $user (@{$hash{one}}){
  print Data::Dumper->Dump([$user],['user']);
 
}
[download]

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