• Knusper@feddit.de
    44·
    10 months ago

    In this thread: Trying to guess the programming language based on a single keyword and angle brackets. 🙃

  • UFO@programming.dev
    16·
    10 months ago

    In Scala:

    case class Fix[F[_]](unfix: F[Fix[F]])
case class Pie[T](filling: T)
def ohNo: Fix[Pie] = Fix(Pie(ohNo))
  • Omega_Haxors@lemmy.ml
    131·
    10 months ago

    is something which is completely unhinged out of context, and sometimes even in context.

  • PetDinosaurs@lemmy.world
    831·
    10 months ago

    Which language are we talking here? Cpp? Because typeof hasn’t ever seemed useful to me in how I use cpp or how I have ever really used a language. I also remember it being criticized in java class more than 20 years ago when OOP was solely preached, even for scientific people like me.

    • mozingo@lemmy.worldEnglish
      391·
      10 months ago

      This sure looks like C#. I use typeof every once in a while when I want to check that the type of a reference is a specific type and not a parent or derived type. But yea, really not that often.

            • sgh@lemmy.ml
              3·
              10 months ago

              Standard C does not have typeof. That’s just a compiler extension…

              Also the equivalent of typeof is most likely decltype or auto.

        • FooBarrington@lemmy.world
          2·
          10 months ago

          Typescript! Though it’s less useful, since the Typescript types aren’t available at runtime, so you’ll just get object for non-primitive values.

        • LapidistCubed@lemmy.world
          21·
          10 months ago

          Probably because Java and C# take much inspiration from C++. They aren’t called “C-based” languages for nothing 😉

      • r00ty@kbin.life
        3·
        10 months ago

        Yeah in C# it has quite a few uses.

        I’m working on a background fun project where there’s a base class that is for olde style CPU emulation. Where you can derive a class from the base class and essentially design 8bit style CPUs.

        I have a separate class as a generic Assembler that will work with any of the created CPUs. But, to be able to do that I need to be able to get information about instructions, arguments, opcodes, registers etc from the derived class.

        So the assembler is instantiated with Assembler\ and then it uses typeof to instantiate the actual CPU class being used to get all the information.

        So, that’s just an example of when you’d use something like this.

    • Konlanx@feddit.de
      23·
      10 months ago

      This is likely referring to TypeScript.

      TypeScript has all of these patterns, they are used very frequently and they are necessary because TypeScript tends to be interesting from time to time since its types only exist at compile time, because it compiles to JavaScript, which is a language without types.

      TypeScript also allows any as a keyword, which says “I don’t know which type this is and I don’t care”, which still produces valid JavaScript. To get back to typed variables it is necessary to use typeof (or similar constructs like a type guard).

      https://www.typescriptlang.org/docs/handbook/2/typeof-types.html

      • jana@leminal.spaceEnglish
        3·
        10 months ago

        But generic type syntax is a feature exclusive to Typescript while typeof is a JavaScript thing. You’d never get Pie[Pie[T]] as a result from a typeof check. (Please excuse the square brackets; seems like the markdown parser here isn’t quite right and it keeps messing up the angle brackets)

        Also, it’s typeof foo not typeof(foo) in js