151
pretty small subtotal. (thelemmy.club)
submitted 1 year ago by [M] to c/software_gore@programming.dev
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[–] 8 points 1 year ago (5 children)

A currency enum and f64

You failed entirely and should not be handling money in code

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  • [+] -8 points 1 year ago (4 children)

    Why? It sounds like you are under the common and false impression that you can't use f64 for money.

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  • [–] 2 points 1 year ago (3 children)

    You can't use it if you ever want to do any operations on said money, due to the loss of prescision.

    Enums are not a good idea for the currencies either.

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  • [–] 0 points 1 year ago* (2 children)

    Yes you can. You're vastly underestimating the size of an f64. Give me a concrete example of a money operation that fails with f64 (for normal companies; assuming you aren't a stock exchange or Visa or whatever).

    Enums are not a good idea for the currencies either.

    Why not?

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  • [–] 3 points 1 year ago (1 child)

    Yes you can. You're vastly underestimating the size of an f64. Give me a concrete example of a money operation that fails with f64 (for normal companies; assuming you aren't a stock exchange or Visa or whatever).

    0.1f64 + 0.2f64 != 0.3f64

    Why not?

    Encoding in assumptions about a fixed amount of supported currencies in a system is broadly speaking not a good idea

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  • [–] 0 points 1 year ago

    0.1f64 + 0.2f64 != 0.3f64

    It does if you round it to the nearest penny.

    Encoding in assumptions about a fixed amount of supported currencies in a system is broadly speaking not a good idea

    Most sensible programming languages allow enums to be non-exhaustive.

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