Don't worry, your moon analogy is fine, but I already know the difference between a reference
and a scalar value. My question has more to do with the
peculiarities of DBI and why it doesn't act like I expect.
See this small example program:
use warnings;
use strict;
use Foo;
use Bar;
my $foo = new Foo;
my $bar = new Bar($foo);
$foo->x("from program");
print "(app) Memory: $foo, X: ".$foo->x()."\n";
$bar->show();
Foo.pm isn't very interesting:
package Foo;
sub new {
my $name = shift;
bless { x => 'from Foo' }, $name;
}
sub x {
my ($self, $arg) = @_;
$$self{x} = $arg if ($arg);
return $$self{x};
}
1;
And Bar.pm just stores some foo:
package Bar;
sub new {
my $name = shift;
my $foo = shift;
bless { foo => $foo }, $name;
}
sub show {
my $self = shift;
my $foo = $$self{foo};
print "(bar) Memory: $foo, X: ".$foo->x()."\n";
}
1;
This example is almost exactly like what I wanted to
do, except that I'm using a makeshift module instead of
DBI.
The results of the memory test will of course depend
upon the execution, but both times the memory location is
the same. That wouldn't happen after I 'forced a copy'
by changing one of the values in $foo if I didn't have
a reference.
I hope this clarifies my question.
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