In a regular expression, all chars between the \Q and \E are escaped. See quotemeta in perlfunc.
In your code sample, you are appending a string, that looks like a regular expression, onto the end of $code.
update
I couldn't find my Perl Cookbook, must have left it at work, however, the code you are referring to is probably assembling a regex so it then can eval it. I seem to remember it was showing some way of performing efficient variable regex's.

In reply to Re: What do \Q and \E mean? by mifflin
in thread What do \Q and \E mean? by apt_get

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