alt Hacker News> I dont really like Python but the ability to make some changes then run it instantly is wild for me.
You'll love Clojure, gets you even closer; you can make changes while your program is running, by changing source code then applying just that function you changed, while your editor is connected to your program and can show what the new results are.
I'm quite often working in a Jupyter notebook where the imported modules are reloaded. I can have x in memory, change method y of X and then call x.y() and get the new definition.
It feels almost criminal that it works, but it's quite nice.