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Clojure has it too.

If you want to abstract the pattern out even further, then all you are doing is running a function within a certain context and then getting everything back to normal. Using under in J, scoping it out with ruby, or using with-open in Lisp are all examples of the pattern, just different ways of thinking about it.

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I think what you're describing is somewhat different: temporarily changing context is like a let block. So for instance in CL you can rebind standard-output to a different stream using let, but then you have to do the legwork to ensure that everything is cleaned up if something goes wrong, while with-open-file or with-output-to-stream will do part of that work.

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