A hacker can replace needed bits in a file, then add other bits so that the overall file checksum stays valid. Doing that gets quantum if you have to hack the subroutines and file checksums.

As for RecDescent, if I could get at the text of a sub I could parse the sub and checksum it myself. The trick is to get at the text of the subroutine. That is where the question lies. Parse::RecDescent needs something like "$text", where $text is the text of the subroutine. You cannot hand it just a coderef. :-)

In reply to Re^2: checksum of subroutine by mnooning
in thread checksum of subroutine by mnooning

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