Zykino

@Zykino@programming.dev

• ⁨Comment⁩ on ⁨Rust is Eating JavaScript⁩ ⁨⁨3⁩ ⁨days⁩ ago⁩:

  First time I hear about checked exceptions. How do you use them ? Are you forced to handle them explicitly ? Is the handling checked at compile time ?

• ⁨Comment⁩ on ⁨Rust is Eating JavaScript⁩ ⁨⁨4⁩ ⁨days⁩ ago⁩:

  3. Is a modern language with a good build system (It’s like night and day compared to CMake)

  Meson exists … as do others.

  But they are not the default option. And your new job may not use them.

  4. And I just like how the language works (errors as values etc.)

  Fair enough; though why? What’s wrong with exceptions?

  Exceptions is a non standard exit point. And by “non standard” I’m not talking about the language but about its surprise appearance not specified in the prototype. Calling double foo(); you don’t know if you should try/catch it, against which exceptions, is it an internal function that may throw 10 level deep ?

  By contrast fn foo() -> Result<f64, Error> in rRst tell you the function may fail. You can inspect the error type if you want to handle it. But the true power of Result in Rust (and Option) is that you have a lot of ergonomic ways to handle the bad case and you are forced to plan for it so you cannot use a bad value thinking it’s good:

  • foo().unwrap() panic in case of error (see also expect)
  • foo().unwrap_or_default() to ignore the error and continue the happy path with 0.0
  • foo().unwrap_or(13.37) to use your default
  • foo()? to return with the error and let the parent handle it, maybe