I think it's a pretty good idea. I can think of a couple things that would keep the impact to the site minimal. First, only check <code> items with a perl shebang line. 2nd, simply put the results of a perl -c in a separate block underneath the block of code in the node. No muss no fuss. Then it doesn't go trying to check a java snippet, or a single subroutine that someone posted, or anything like that.

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naChoZ