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Joined 10 months ago
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Cake day: November 26th, 2023

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  • You use lifetimes to annotate parameters and return values in order to tell the compiler about how long things must last for your function to be valid. You can link a specific input with the output, or explicitly separate them. If you don’t give lifetimes the language uses some basic rules to do it for you. If it can’t, eg it’s ambiguous, then it’s a compile error and you need to do it manually.

    It’s one of the harder concepts of rust to explain succinctly. But imagine you had a function that took strA and strB, used strB to find a subsection of strA, and then return a slice of strA. That slice is tied to strA. You would use 'a annotation for strA and the return value, and 'b for strB.

    Rust compiler will detect the lifetime being shorter than expected.


    Also, ownership semantics. Think c++ move semantics. Only one person is left with a good value, the previous owners just have garbage data they can’t use anymore. If you created a thing on the heap and then gave it away, you wouldn’t have it anymore to free at the end. If you want to have “multiple owners” then you need ref counting and such, which also stops this problem of premature freeing.


    Edit: one more thing: reference rules. You can have many read-only references to a thing, or one mutable reference. Unless you’re doing crazy things, the compiler simply won’t let you have references to a thing, and then via one of those references free that thing, thereby invalidating the other references.



  • mhague@lemmy.worldtoProgrammer Humor@lemmy.mlThanks ...
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    5 months ago

    I don’t see a negative. It’s foss so you ought to be relaxed about others using your code. The issues are probably just articulating problems that were already there. If it’s stuff you don’t care about… it’s a foss repository so you just ignore it.



  • Not SO or it’s methods, I mean the human experience. It can be awkward to be new to it all and to feel the frustration/tunnel vision associated with being stuck on one problem… and then step back and have to dissect your issue, structure your question correctly, etc.

    It’s just how it is, for exactly the reasons you stated. You can capture every little problem people face in programming, or you can hone in on useful patterns in goals, problems, and solutions, and educate people on how to see these things.


  • mhague@lemmy.worldtoTechnology@lemmy.worldStack Overflow and OpenAI Partner
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    5 months ago

    The idea of SO is a little awkward too I think. With something like Wikipedia we’re presumably in an academic mindset. Carefully gathering information, sources, structuring it all. And even then people can get turned off by the ‘bureaucracy’ or nitpicking or whatever.

    When people show up at SO they’re probably more in a “I can’t figure this damn thing out!” mode. We’re struggling with a problem, keeping a bunch of junk in our head, patience being tested, but we’re still expected to have a bit of academic rigor in our question and discourse.


  • mhague@lemmy.worldtoTechnology@lemmy.worldStack Overflow and OpenAI Partner
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    5 months ago

    Yeah but a lot of people don’t really know what SO is for. They think you just go there and get help and call it a day. But the entire point is to produce structured questions, discourse, and answers aimed at future readers. Super specific, no-context, or duplicate problems are not useful. If you are not trying to generate useful content, don’t go to SO.

    Just look at all the people getting frustrated at being told “you should probably do it a different way.” They really don’t understand that just because they’re asking the question, it’s not all about them.