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Comment by maxiepoo | Hacker News Reader

I believe this is a design decision, because relying on some enormous implicit repl state and updating the code in place is a good way to get yourself into states that are impossible to reach in an actual running program. Racket is a functional language and it is their belief that you should just make predictable ways to startup your interactive development than rely on the entire state of some repl image.

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You're right; it's a conscious decision. I had a little discussion with Eli Barzilay and Matthew Flatt about some related matters a little while back. It was a nice discussion, but image-based or live programming is just not something they found particularly compelling.

It pretty much keeps me from using Racket, and a bunch of other things that are otherwise very nice. Given a choice, I will always choose the tools that support me in building things by modifying programs as they run. I'm just happier and more productive that way.

So one of my axes of optimization is selecting projects that enable me to work that way.

My thoughts exactly. Once you are used to this way of developing, it is really difficult to be happy with less.

Ah yes, I remember seeing an interaction that was probably yours, tried to find it for my comment, but never did.

I don't know what this refers to, but it doesn't ring a bell. The most I might have said is that the community in general is not too interested; but personally, this kind of dynamic interaction is something that I very much appreciate. In fact, when I implemented xrepl (which is now the default when you start racket) being able to modify code inside modules was one of the main goals. The only reason I didn't do something like that for Emacs is that my own use of CL/Scheme variants in Emacs was always very simple, but I actively encouraged people to do something similar for Emacs -- and Geiser/Racket-mode are two serious Emacs packages that actually do that kind of interactive use.

I asked you guys about image-saving because I was considering using Racket to build a new version of bard, and I thought I might like to both use image-saving during development and piggyback on a Racket implementation of it for use in bard's runtime. As I recall, you guys wanted to know what I found compelling about image-saving, but you didn't find it as compelling as I did.

I still might build a bard on Racket, but if so, I'll most likely build my own VM and implement my own image-saving solution for it.

Assuming, of course, that there are enough hours in the day, and enough years in a life.

I'm not sure if this is exactly what you are talking about, but with racket-mode in Emacs you can write some program, run it (C-c C-k), then add some s-expr and evaluate only that (C-x C-e) in the current context.

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