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by fiddlerwoaroof 927 days ago
I think it’s basically impossible to safely live-patch part of a compilation unit in most programming languages: you’d have to account for inlining and other optimizations to do this correctly. You _can_ patch at linkage seams and other places, but this is a fraction of the sorts of redefinitions that you get easily in systems designed for it. (And I’ve spent a lot of time trying to make various programming languages more Lispy so I can get stuff done: you always discover there are static presumptions that make it impossible to get the full experience)
1 comments

> I think it’s basically impossible to safely live-patch part of a compilation unit in most programming languages

There's no argument there; you're right. That's why V and Nim, for example, put reloadable things in a separate compilation unit and handle some things (global state at least) specially upon reload (if I understand what they do correctly.)

My point was that you can get quite close (sometimes with a massive pile of hacks and/or developer inconvenience), not that you can get the full experience (as in Smalltalk or Lisp) everywhere. Especially since the reloading being convenient is a large part of the experience, I think.