alt Hacker NewsI think the article names hashing as a use-case, which I can somewhat still agree. Operations that only depend on the bytes, I guess. But yeah, most things worth saying about this article have been said here already
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xigoi • today at 4:27 PM
Hashing everything based on the byte representation breaks when you have a type where equality does not imply byte equality. Such as… floats (+0 and -0 are equal, but have different byte representation).
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throwaway27448 • today at 4:20 PM
Even then, accepting a uint8_t* would make this intent clearer.
Sure, if the function is expected to not treat the data as anything but bytes, then it might be acceptable in narrow circumstances.
But in such a case I'd argue FOR the ceremony, as a way of declaring from the API "The input is a sequence of bytes that I won't treat as anything other than a sequence of bytes", and declaring from each and every call site: "This is not a mistake; we really are 'converting' this struct to a series of bytes for this function to consume".
Then anyone auditing the code knows the intent by the shape of the types, and would quickly flag any typecasting shenanigans within the receiver function.
But even then, hashing a struct will rapidly bring you into the land of dragons and fairies. Abandon all hope if you have floats or UTF-8 (which have multiple representations for the same values).
Far better to remain type-aware if you value your sanity.