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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: 0.212s | source
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EastLondonCoder ◴[31 Oct 25 09:30 UTC] No.45770007[source]▶
After a 2 year Clojure stint I find it very hard to explain the clarity that comes with immutability for programmers used to trigger effects with a mutation.

I think it may be one of those things you have to see in order to understand.

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1. ratelimitsteve ◴[31 Oct 25 19:41 UTC] No.45775905[source]▶
the flash of enlightment I had when I understood the incredible power the rules of functional programming give you as a coder is probably the biggest one I've had in my career so far. idempotence, immutability and statelessness on their own let you build a thing once in a disciplined way and then use it all willy nilly anywhere you want without having to think about anything other than "things go into process, other things come out" and it's so nice.