If learning lisp is important "not because you'll use it but because it will forever change you" (to paraphrase) then learning Smalltalk is important in the sam

If learning lisp is important "not because you'll use it but because it will forever change you" (to paraphrase) then learning Smalltalk is important in the same way. Learning Common Lisp is like learning Smalltalk in another way, Common Lisp shares some of Smalltalk's features. For instance, if I messed up something in my code and had an error, the debugger pops up. In this debugger I can not only browse the stack trace and manipulate those objects, I can actually fix what is broken and resume execution of the program from that point. This is also true for Common Lisp. When I hit a bug, I can edit the broken code, reload it, and resume execution from where the program stopped. I can load edited code and freeze the program to inspect objects at any time. It's enjoyable to edit some opengl code and see changes in real time. I used to use Light Table with Clojure and Javascript to kind of recreate the effect, but what the author writes is true: abandoning your familiar textual tools lets you do some really awesome things. It completely changes your development and debugging workflow. If anyone was wondering why some people don't like Clojure being described as a modern Lisp or the future of Lisp, this is one reason.