I don't mind the disallowing name shadowing, but I really, really hate (I mean that) websites that are just good ol' text and the odd picture that require Javascript. The excuse of "we used React, it's easy" seems odd given that HTML is much easier.
But I agree, this can be cumbersome. So, Flix allows any unused construct to be prefixed with an underscore to mark it as unused. (But underscored things cannot be referenced.) This seems like a pragmatic trade-off.
(I am one of the developers of Flix).
What benefit does it have in development-mode?
Any language that does it, is beyond usable (notably go and zig). Like, I would literally fork the compiler before using them with that “feature” on. It’s completely braindead thing to do — like okay, have a separate production release mode and make it an error there. But for quickly testing out stuff, you will inevitably comment something out, which makes a variable unused. Commenting that out will also make something else unused, so you literally have a recursive problem with some random depth, and depending on how deep it goes, you will literally lose all of the context on what you wanted to debug in the first place.
There is literally zero advantage of this idiotic bullshit, my proposed solution of doing it only in prod release gives all the benefits with none of the negatives.
It is a brain-dead feature, verbatim if you prefer that word.
But feel free to give me the nuance to this design issue that you so miss.
It produces warnings for unused variables, and warnings become errors, when you want to compile a production executable with -prod , so you can get both the benefit of prototyping without losing your flow, and you are still required to cleanup after that, when you are finished, before release.
Make those warnings in debug/test builds, and errors in prod builds.