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John Carmack on mutable variables

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498 points azhenley | 1 comments | 31 Oct 25 02:34 UTC | HN request time: 0.329s | source
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munchler ◴[31 Oct 25 02:54 UTC] No.45767832[source]▶
> Making almost every variable const at initialization is good practice. I wish it was the default, and mutable was a keyword.

It's funny how functional programming is slowly becoming the best practice for modern code (pure functions, no side-effects), yet functional programming languages are still considered fringe tech for some reason.

If you want a language where const is the default and mutable is a keyword, try F# for starters. I switched and never looked back.

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1. johncolanduoni ◴[31 Oct 25 03:51 UTC] No.45768230[source]▶
I’ve done a significant amount of functional programming (including F#) and still reach for it sometimes, but I don’t think it provides substantial advantages for most use-cases. Local mutability is often clearer and more maintainable.

Also, category theorists think how excited people get about using the word monad but then most don’t learn any other similar patterns (except maybe functors) is super cringe. And I agree.