sub another_func {
  my $ref = CreateRef();
  # do things with $ref
  return 1;
  # $ref goes out of scope here and so we lose our last
  # reference to the hash and it is freed.
}

sub CreateRef {
  my %some_hash = ('foo' => 'bar');
  return \%some_hash;
  # We lose the 'some_hash' name reference to
  # the 'some_hash' data, but we have created another
  # reference (the return value) so the data lives...
}
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# Note use of {} (same as for accessing hash elem)
my $ref_to_anon_hash = { foo => 'bar' };
# Note use of () (same as for accessing array elem)
my $ref_to_anon_array = [ 1, 2 ];
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sub leak_mem {
  my $foo;  # foo data has one reference, the 'foo' name
  my $bar;  # bar data has one reference, the 'bar' name
  $foo = \$bar;  # bar data has two refs
  $bar = \$foo;  # foo data has two refs
  return 1;
  # Oops. foo and bar data reference count are both
  # decremented by one (because the foo and bar names have
  # just gone out of scope), but that doesn't take them
  # to zero.
  # We just lost some bytes, sir.
}
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