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John Carmack on mutable variables

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498 points azhenley | 2 comments | 31 Oct 25 02:34 UTC | HN request time: 0.424s | 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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brrrrrm ◴[31 Oct 25 03:44 UTC] No.45768188[source]▶
one thing I've learned in my career is that escape hatches are one of the most important things in tools made for building other stuff.

dropping down into the familiar or the simple or the dumb is so innately necessary in the building process. many things meant to be "pure" tend to also be restrictive in that regard.

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1. runevault ◴[31 Oct 25 03:50 UTC] No.45768228[source]▶
Functional languages are not necessarily pure though. Actually outside Haskell don't most functional first languages include escape hatches? F# is the one I have the most experience with and it certainly does.
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2. gf000 ◴[31 Oct 25 09:57 UTC] No.45770194[source]▶
For what it's worth, Haskell has plenty of escape hatches itself as well.