Two more cents worth:

Playing around with "manufactured" references like

no strict 'refs';
$value = ${$foo . $bar}
[download]

is fine and useful for one-off scripts. It might even be acceptable in a standalone application, if you are careful about what $foo and $bar are.

However, it is almost certainly begging for disaster in a CGI script unless you carefully validate your input, and the code you spend doing that would probably end up being longer than the code necessary to do it a better way (with a hash, as suggested above, for one).

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"I hate it when I think myself into a corner."
Matt Mitchell