If you have a lot of delayed building of contained objects, for example. I worked in one place that deferred every single thing that could be deferred. It was nice, unless you needed to get something from the root node. It then build everything all at once. Talk about a smack in the face!

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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.