What are invariants, how can they be used, and have you ever used it in your program?

Posted by gablin on Programmers See other posts from Programmers or by gablin
Published on 2010-12-30T21:19:20Z Indexed on 2010/12/30 22:00 UTC
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invariants

I'm reading Coders at Work, and in it there's a lot of talk about invariants. As far as I've understood it, an invariant is a condition which holds both before and after an expression. They're, among other things, useful in proving that loop is correct, if I remember my Logic course correctly.

Is my description correct, or have I missed something? Have you ever used them in your program? And if so, how did they benefit?

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