That's not always true. There are times a module might consider something a failure, but the caller might not. For example, I have a program that uses die to throw signals that aren't exceptions. While I don't have it coded this way, I could easily see using that facility of Error.

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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.