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      And here’s a video that wonderfully shows how handler-bind, that does not unwind the stack, is useful in the day to day to save your butt: you got an error, you fix it without quitting the interactive debugger, re-compile the function, resume execution from any point in the stack. https://www.youtube.com/watch?v=jBBS4FeY7XM (shameless plug)

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        The Condition System is amazing for writing libraries and reusable code, it really is a shame no other language has taken another crack at it. It’s also worth linking the chapter “Beyond Exception Handling” from Practical Common Lisp (which I am obliged to recommend as it is both excellent and free).

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          In my opinion, this is one of the few things Common Lisp still has over and beyond any contemporary language.