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   Sexy Moon (moon@shitposter.club)'s status on Wednesday, 25-Oct-2023 00:10:15 JST Sexy Moon
   C > C++
   • Haelwenn /элвэн/ :triskell:, Doughnut Lollipop 【記録係】:blobfoxgooglymlem: and Pleroma-tan like this.
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     Trash Panda (raccoon@den.raccoon.quest)'s status on Wednesday, 25-Oct-2023 00:11:15 JST Trash Panda

     in reply to

     @Moon@shitposter.club Mathematically impossible since one has plus and the other does not.

     Pleroma-tan likes this.
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     Doughnut Lollipop 【記録係】:blobfoxgooglymlem: (tk@bbs.kawa-kun.com)'s status on Wednesday, 25-Oct-2023 00:26:31 JST Doughnut Lollipop 【記録係】:blobfoxgooglymlem:

     in reply to

     @Moon What about B?

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     :umu: :umu: (a1ba@suya.place)'s status on Wednesday, 25-Oct-2023 00:30:07 JST :umu: :umu:

     in reply to
     @Moon true tho.
     
     C++ std committee is non-stopping printer of bad ideas
     Sexy Moon and :blobancap: :blobcattrans: :blobancap: :blobcattrans: :blobancap: :blobcattrans: like this.
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     :umu: :umu: (a1ba@suya.place)'s status on Wednesday, 25-Oct-2023 00:31:43 JST :umu: :umu:

     in reply to

     • :suya:
     • :umu: :umu:
     @Moon sure, you can make a subset of C++ like @newt said, but it's either limiting yourself to C++98, either keeping eye that everyone involved does write in that C++ subset because there are no tools to selectively disable C++ features. The closest are static analyzers that can check against MISRA C++ guidelines, but that's it.
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     narcolepsy and alcoholism :flag: (hj@shigusegubu.club)'s status on Wednesday, 25-Oct-2023 00:33:01 JST narcolepsy and alcoholism :flag:

     in reply to
     @Moon false
     
     because C will be incremented comparison operation completes, not before
     Haelwenn /элвэн/ :triskell: likes this.
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     Sexy Moon (moon@shitposter.club)'s status on Wednesday, 25-Oct-2023 01:36:45 JST Sexy Moon

     in reply to

     • narcolepsy and alcoholism :flag:
     Pretty sure undefined behavior
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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Wednesday, 25-Oct-2023 02:30:03 JST Haelwenn /элвэн/ :triskell:

     in reply to

     • narcolepsy and alcoholism :flag:
     @Moon @hj Nah, I'm pretty sure i++ vs. ++i is well defined in C.
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     Sexy Moon (moon@shitposter.club)'s status on Wednesday, 25-Oct-2023 02:30:28 JST Sexy Moon

     in reply to

     • Haelwenn /элвэн/ :triskell:
     • narcolepsy and alcoholism :flag:
     @lanodan @hj I guess we could look
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     ロミンちゃん (romin@shitposter.club)'s status on Wednesday, 25-Oct-2023 02:32:53 JST ロミンちゃん

     in reply to

     • Haelwenn /элвэн/ :triskell:
     • narcolepsy and alcoholism :flag:

     @Moon @lanodan @hj it’s assigning the increment the one that it’s undefined (i = i++;)

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     narcolepsy and alcoholism :flag: (hj@shigusegubu.club)'s status on Wednesday, 25-Oct-2023 02:33:07 JST narcolepsy and alcoholism :flag:

     in reply to

     • Haelwenn /элвэн/ :triskell:
     @Moon @lanodan the joke is that even if it was c > ++c it would still be false because c is incrementing, not decrementing
     
     equals though is a different story.
     
     at least in JS:
     a === ++a
     false
     a === a++
     true
     
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     narcolepsy and alcoholism :flag: (hj@shigusegubu.club)'s status on Wednesday, 25-Oct-2023 02:45:04 JST narcolepsy and alcoholism :flag:

     in reply to

     • Haelwenn /элвэн/ :triskell:
     • applejack 🇮🇸:hitlergrin2:
     @applejack @lanodan @Moon
     a > ++a === undefined
     false
     
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     applejack 🇮🇸:hitlergrin2: (applejack@gameliberty.club)'s status on Wednesday, 25-Oct-2023 02:45:05 JST applejack 🇮🇸:hitlergrin2:

     in reply to

     • Haelwenn /элвэн/ :triskell:
     • narcolepsy and alcoholism :flag:

     @hj @lanodan @Moon It's not false or true, it's completely undefined. The rules for sequencing explicitly state that you can only update a variable once between sequence points

     The compiler is allowed to read C into register B, then increment C in place, then read C into register A, and then conclude that A > B

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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Wednesday, 25-Oct-2023 02:47:38 JST Haelwenn /элвэн/ :triskell:

     in reply to

     • narcolepsy and alcoholism :flag:

     @hj @Moon Meanwhile in reality rather than code: C !== C++
     As C++ is long gone from being a pure superset of C, both evolved in their own ways.

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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Wednesday, 25-Oct-2023 03:16:49 JST Haelwenn /элвэн/ :triskell:

     in reply to

     • narcolepsy and alcoholism :flag:
     • LEdoian
     @ledoian @hj @Moon Ooh… yeah that part might be.
     And yeah C is a language where clever-code/code-golfing will just result in broken behavior, I don't think I would do a comparaison and an increment at the same time in actual code.
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     LEdoian (ledoian@pleroma.ledoian.cz)'s status on Wednesday, 25-Oct-2023 03:16:51 JST LEdoian

     in reply to

     • Haelwenn /элвэн/ :triskell:
     • narcolepsy and alcoholism :flag:

     @lanodan @hj @Moon I think the comparison might be actually undefined, since there is no sequence point in that expression, so it is possible that the RHS is evaluated before LHS, thus resulting in true. (Or house fire, given it is UB…)

     One of the favourite gotchas of C… I only remember: when pre-/postincrementing, do not do anything clever like reusing the variable. And I had to check the standard to be at least slightly confident in what I write here.