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Comment by sigstoat | Hacker News Reader

> When I investigated it, there seemed to be no way to actually connect a repl to a running program.

i (poorly) implemented conditions for racket once, including the ability to drop into a repl at the point of error.

so i think you could put in place some macros that would let you get at a repl wherever you wanted. probably not the sort of thing to leave in place all the time, though

> Unlike with common lisp or clojure, with racket if you make changes to your code you have to restart the REPL, which destroys your state.

that's a different issue. i believe matthias has commented on the mailing list (some years back) that the semantics associated with doing something like that are a mess, and that's why they weren't interested in implementing it.

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To me, being able to make changes to your code while keeping the current state in the REPL is key to interactive development.

My workflow is generally to build up state, and then experiment with functions on that state until I get the correct output.

This workflow is very natural in Clojure, Common Lisp and even Python (with IPython and autoreload).

However, in Racket you have to restart everything on every change. This works ok for smaller applications, but if for example, your state is a large dataset that you pull from a remote database, it becomes a little more difficult.

There are possibly workarounds, and I'm not saying that Racket is bad because of this. There are definite advantages to this approach, mainly for keeping everything simple and predictable. However, this was a roadblock for me, and the main reason why I didn't spend more time working on it.

I also miss the ability to make changes to code, refresh the browser and instantly see the changes (instead of having to restart the server after each change).

Here's a good discussion (in my opinion) of what makes a good REPL for interactive development: http://vvvvalvalval.github.io/posts/what-makes-a-good-repl.h...

It isn't in DrRacket by default but it is a common enough requested feature that they keep an example of how to add it in the documentation.

https://docs.racket-lang.org/drracket/Keyboard_Shortcuts.htm...

Thanks. Do you know if it works with the module system - for example, if I edit function definition in a module, and then send that module definition to the REPL, would any code using that module start using the new definition?

It works in geiser-mode, i don't know if it works with drracket or racket-mode.

http://docs.racket-lang.org/guide/eval.html?q=namespace#%28p...

I'm surprised no one has mentioned geiser. It sounds like exactly what you want for racket. http://nongnu.org/geiser/geiser_3.html

There is also racket-mode (available on MELPA): https://github.com/greghendershott/racket-mode

This is what I use. I find it quite comfortable / very easy to get going.

Geiser is fine. However, we can’t compare it with SLIME. The integration of the latter is much better.

I use Visual Studio Code for Racket. https://marketplace.visualstudio.com/items?itemName=karyfoun...

Before that I would use VIM with a tiled window manager that worked really well.

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