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.
But if you comment out the line
$hash{blah} = 1;
Everything works as expected. FETCH returns an anonymous array and foreach properly iterates through it printing out the following:
$user = {
'val' => 1
};
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']);
}
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