Tie'ing variables

Hi,

Analyzing PHP's routines a bit, it seems that the slowest part of a
"generic" request is populating the special arrays, $_ENV, $_GET, etc.

I was wondering if it might be possible to "tie" these arrays to a
function (if you don't understand that, look at Perl for a definition). 
One could populate them as an overloaded object, and then array accesses
would work - I guess.  But I would prefer a cleaner mechanism.

This would prevent a costly overhead for elements that don't really need
to be there, and yield only a slight performance cost when accessing
overloaded elements in these arrays.

-Sterling

-- 
"The computer programmer is a creator of universes for which he  
 alone is responsible. Universes of virtually unlimited complexity  
 can be created in the form of computer programs." 
    - Joseph Weizenbaum