This is a very nice example. However, you shouldn't have declared $cmd lexically--doing so means that your example isn't very dangerous at all. :)

Because that for loop overwrites $main::cmd... not the lexical $cmd that you've already defined. When you use $cmd w/o using a package qualifier, you're using the lexical $cmd, if one exists--and one does exist, in this case. So you're still just doing 

    system "ls";

[download]
Make your $cmd a package global, and then it's dangerous again.

Of course, your point is made either way. :)

In reply to RE: Re: Putting HTML fieldnames in symbol space by btrott
in thread Putting HTML fieldnames in symbol space by Russ

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