> Really what this convo is doing is underscoring for me how there really is nothing more to be learned from lisp - I had a lingering doubt that I'd missed some aspect but you guys are all repeating the same thing over and over.
No, you keep on misunderstanding what people are trying to tell you. It’s a communication failure. The thing that you think you are doing in Python is not the thing that people are doing in Lisp.
As an example, I suppose that when you’re developing code in Python’s pseudo-REPL you often reimport a file containing class definitions. When you do that, what happens to all the old objects with the old class definition? Nothing, they still belong to the old class.
If you did this on a REPL connected to a server, what would happen to the classes of objects currently being computed on? Nothing, they would still belong to the old class.
In Lisp, it’s different. There is a defined protocol for what happens when a class is redefined. Every single object belonging to the old class gets updated to the new class. You can define code to get called when this happens (say, you added a new mandatory field, or need to calculate a new field based on old ones — and of course ‘calculate’ could also mean ‘open a network connection, dial out to a database and look up the answer’ or even ‘print the old object and offer the system operator a list of options for how to proceed’). And everything that is currently in-flight gets updated, in a regular and easy-to-understand way.
People are telling you ‘with Lisp central air conditioning, I can easily heat my house in the winter’ and you are saying ‘with Python, I can easily build a fire whenever my house gets cold too!’
No, you keep on misunderstanding what people are trying to tell you. It’s a communication failure. The thing that you think you are doing in Python is not the thing that people are doing in Lisp.
As an example, I suppose that when you’re developing code in Python’s pseudo-REPL you often reimport a file containing class definitions. When you do that, what happens to all the old objects with the old class definition? Nothing, they still belong to the old class.
If you did this on a REPL connected to a server, what would happen to the classes of objects currently being computed on? Nothing, they would still belong to the old class.
In Lisp, it’s different. There is a defined protocol for what happens when a class is redefined. Every single object belonging to the old class gets updated to the new class. You can define code to get called when this happens (say, you added a new mandatory field, or need to calculate a new field based on old ones — and of course ‘calculate’ could also mean ‘open a network connection, dial out to a database and look up the answer’ or even ‘print the old object and offer the system operator a list of options for how to proceed’). And everything that is currently in-flight gets updated, in a regular and easy-to-understand way.
People are telling you ‘with Lisp central air conditioning, I can easily heat my house in the winter’ and you are saying ‘with Python, I can easily build a fire whenever my house gets cold too!’