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

(www.open-std.org)
182 points Twirrim | 1 comments | 17 Oct 24 22:21 UTC | HN request time: 0s | source
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WalterBright ◴[18 Oct 24 00:33 UTC] No.41875254[source]▶
D made a great leap forward with the following:

1. bytes are 8 bits

2. shorts are 16 bits

3. ints are 32 bits

4. longs are 64 bits

5. arithmetic is 2's complement

6. IEEE floating point

and a big chunk of wasted time trying to abstract these away and getting it wrong anyway was saved. Millions of people cried out in relief!

Oh, and Unicode was the character set. Not EBCDIC, RADIX-50, etc.

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gerdesj ◴[18 Oct 24 01:10 UTC] No.41875486[source]▶
"1. bytes are 8 bits"

How big is a bit?

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1. nonameiguess ◴[18 Oct 24 03:14 UTC] No.41876060[source]▶
How philosophical do you want to get? Technically, voltage is a continuous signal, but we sample only at clock cycle intervals, and if the sample at some cycle is below a threshold, we call that 0. Above, we call it 1. Our ability to measure whether a signal is above or below a threshold is uncertain, though, so for values where the actual difference is less than our ability to measure, we have to conclude that a bit can actually take three values: 0, 1, and we can't tell but we have no choice but to pick one.

The latter value is clearly less common than 0 and 1, but how much less? I don't know, but we have to conclude that the true size of a bit is probably something more like 1.00000000000000001 bits rather than 1 bit.