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C++ proposal: There are exactly 8 bits in a byte

(www.open-std.org)
288 points Twirrim | 1 comments | 17 Oct 24 22:21 UTC | HN request time: 0.207s | source
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favorited ◴[17 Oct 24 23:54 UTC] No.41875023[source]▶
Previously, in JF's "Can we acknowledge that every real computer works this way?" series: "Signed Integers are Two’s Complement" <https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p09...>
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jsheard ◴[18 Oct 24 00:25 UTC] No.41875200[source]▶
Maybe specifying that floats are always IEEE floats should be next? Though that would obsolete this Linux kernel classic so maybe not.

https://github.com/torvalds/linux/blob/master/include/math-e...

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seoulbigchris ◴[18 Oct 24 08:27 UTC] No.41877394[source]▶
Which one? Remember the decimal IEEE 754 floating point formats exist too. Do folks in banking use IEEE decimal formats? I remember we used to have different math libs to link against depending, but this was like 40 years ago.
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quietbritishjim ◴[18 Oct 24 10:59 UTC] No.41878213[source]▶
Nothing prevents banks (or anyone else) from using a compiler where "float" means binary floating point while some other native or user-defined type supports decimal floating point. In fact, that's probably for the best, since they'll probably have exacting requirements for that type so it makes sense for the application developer to write that type themselves.
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1. seoulbigchris ◴[18 Oct 24 15:42 UTC] No.41880459[source]▶
I was referring to banks using decimal libraries because they work in base 10 numbers, and I recall a big announcement many years ago when the stock market officially switched from fractional stock pricing to cents "for the benefit of computers and rounding", or some such excuse. It always struck me as strange, since binary fixed and floating point represent those particular quantities exactly, without rounding error. Now with normal dollars and cents calculations, I can see why a decimal library might be preferred.