how so?

replacing an existing value would be simply: 

$my_ordered_hash{$old_key} = $newvalue;

[download]
would be implemented as: 
sub STORE
{
    my( $this, $key, $val ) = @_;
    if ( exists( $this->{hash}->{$key} ) )
    {
        $this->{hash}->{$key} = $val;
    }
    else
    {    $this->{hash}->{$key} = $val;
        push @{$this->{order}}, $key; 
    }    
}

[download]
...since replacing a value for an existing key should not (in this case) change its order. if you did want this behaviour ie STOREing a value *always* appends to the end, then the performance of STOREing with this implementation gets a little ugly -- O(n), for the array scan.

the only really messy problem with this implementation is DELETEing - since that requires array scanning and splicing.

is there any other complications?

In reply to RE: RE: RE: Re: Hash Internals by d_i_r_t_y
in thread Hash Internals by orthanc

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