BrowserUk,
The second is you also need to store unsmashed copies of the references so that perl will not GC the elements to which you are storing smashed refs. That duplication of storage negates much of the benefit,...

tye was quick to point out an easy solution for the problem was to use a parallel hash as a lookup table. I admitted it was a good straight forward answer but defeated my purpose. On the other hand if an anonymous sub can be made to take up less space than the anonymous array: 

sub compact {
    my $ref = shift;
    my $pck;  # Packed information except reference

    # purposefully avoiding dispatch table
    # This keeps us at HoC
    return sub {
        if    ( $_[0] eq 'data' ) { return $ref };
        elsif ( $_[0] eq 'blah' ) { return unpack('A1', $pck) }
        # where each unpack format gets desired data
    };
}

$hash{foo} = compact( [1..10] );
$hash{foo}->( 'data' )[3] = 42;

[download]

The interface could use work and it doesn't really explore any uncharted territory for me. It also is still not a single hash. We are just trading anonymous subs for anonymous arrays.

Cheers - L~R

In reply to Re^2: Techniques On Saving Memory by Limbic~Region
in thread Techniques On Saving Memory by Limbic~Region

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