cpan-purity is a fairly sweet perl hack I just wrote. Test how much of a the guts of a program comes from sweet, delicious CPAN, and how much is nasty perl code you wrote. 
joey@dragon:~>./cpan-purity -- ./cpan-purity
usage: cpan-purity [--verbose] [--mine=regexp] -- program args
** CPAN Prurity test results: 98.08% pure CPAN code.
** 7107 lines in 24 files were from CPAN, and 139 lines in 1 files wer
+enot.

joey@dragon:~>./cpan-purity -- perl -e 'use Coy; die "whups, gotta go.
+."'

        -----
        Two rabbits walk. A
        pair of lovers beside a pool.
        A trout in the dam.
        -----

                Homer Simpson's commentary...

                whups, gotta go..

                        (Sayings of -e: line 1.)
** Looks like that was a perl one-liner..
** CPAN Prurity test results: 99.98% pure CPAN code.
** 6028 lines in 16 files were from CPAN, and 1 lines in 0 files were 
+not.

joey@dragon:~>./cpan-purity --mine=debconf -- dpkg-preconfigure
dpkg-preconfigure: must specify some debs to preconfigure
** CPAN Prurity test results: 70.49% pure CPAN code.
** 6745 lines in 41 files were from CPAN, and 2823 lines in 20 files w
+ere not.

[download]
Also useful with -v. Enjoy!

Edited by planetscape - removed pre tags, replaced with <code></code> tags

In reply to CPAN Purity tester by joey

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