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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: 0.208s | source
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anymouse123456 ◴[31 Oct 25 13:50 UTC] No.45771965[source]▶
I completely agree with the assertion and the benefits that ensue, but my attention is always snagged by the nomenclature.

I know there are alternate names available to us, but even in the context of this very conversation (and headline), the thing is being called a "variable."

What is a "variable" if not something that varies?

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garethrowlands ◴[31 Oct 25 14:01 UTC] No.45772077[source]▶
The term 'variable' is from mathematics. As others have said, the values of variables do vary but they do not mutate.
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1. astrobe_ ◴[31 Oct 25 17:17 UTC] No.45774378[source]▶
Yes, and math has the notion of "free variable" and "bound variable" [1].

[1] https://en.wikipedia.org/wiki/Free_variables_and_bound_varia...