This is really interesting - exactly 2 years later, I've dropped and reapproached the problem completely differently. This time, I actually have something working and (soon) postable to CPAN. Also, the design is much simpler and extensible. Wow ...

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We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.