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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: 0.209s | source
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stevage ◴[31 Oct 25 03:51 UTC] No.45768231[source]▶
In JavaScript, I really like const and have adopted this approach. There are some annoying situations where it doesn't work though, to do with scoping. Particularly:

- if (x) { const y = true } else { const y = false } // y doesn't exist after the block - try { const x = foo } catch (e) { } // x doesn't exist after the try block

replies(4): >>45768310 #>>45768515 #>>45768529 #>>45771225 #
askmrsinh ◴[31 Oct 25 04:44 UTC] No.45768515[source]▶
Why not do:

const y = x ? true : false;

replies(2): >>45768564 #>>45773065 #
1. 1718627440 ◴[31 Oct 25 15:22 UTC] No.45773065[source]▶
That sounds like a more complicated way to write

    const y = (bool)x;
or

    const bool y = x;