I was frightened today. A co-worker showed me some code from a client. We are co-developing a site with him. He apparently does this all the time: 
foreach $key (CGI::param()) { ${$key} = CGI::param($key) }

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(Assigning the HTML field name to the symbol table)

Now, he can use the HTML field names as variables (e.g. $Username, $Password, etc.) My co-worker defended this idea, saying it is entirely normal (he did it "all the time" in TCL), and that this feels much more readable to him.

So, my question: is this a "normal" thing to do (and I've just never stumbled across the idea) or am I right to have my skin crawl thinking of this?

This just can't be a "good thing," but it's not my code and not my project, so...

<cringing>Russ</cringing>

P.S. I explained the dangers of messing with the symbol table, the risks that someone will name a field (in HTML) to a used/reserved name in Perl, and the loss of maintainability (a variable which just "magically" appears without being referenced anywhere should confuse people). I told him it is considered good practice to run with 'use strict', and that this will not. In the end, I conceded that "yes, the code will work that way..." and our client wrote it, so...

In reply to Putting HTML fieldnames in symbol space by Russ

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