Is it just me, or does Rust feel much more bare-bones than other languages? I just started learning it recently and this is the one thing that stood out to me, much more so than the memory management business. A lot of things that would normally be part of the language has to be achieved through meta-programming in Rust.

Is this a deliberate design choice? What do we gain from this setup?

Edits:

  1. Somehow, this question is being interpreted as a complaint. It’s not a complaint. As a user, I don’t care how the language is designed as long as it has a good user experience, but the curious part of my mind always wants to know why things are the way they are. Maybe another way to phrase my question: Is this decision to rely more on meta-programming responsible for some of the good UX we get in Rust? And if so, how?
  2. I’m using meta-programming to mean code that generates code in the original language. So if I’m programming in Rust, that would be code that generate more Rust code. This excludes compilation where Rust gets converted into assembly or any other intermediate representation.
  • TehPers@beehaw.orgEnglish
    3·
    22 hours ago

    You can design a language where you don’t need to generate code to accomplish this.

    Depending on what you mean by “generate code”, the only language at the level of C or C++ that I can think of that does this is Zig. Zig is weird though because you’re still doing what is functionally compile-time reflection, so in a way you’re still generating code, just in a different way.

    If you’re comparing to Python, JS, or even C#, those all come with runtimes that can compile/interpret new code at runtime. None of those languages are comparable here. Rust, C, C++, Zig, etc compile into assembly, and type information, impl information, etc are all lost after compilation (ignoring symbol names or anything tracked as debug info).

    If you’re specifically referring to Debug, Display, PartialEq, etc then the compiler doesn’t do that for you because Rust doesn’t assume that those traits are valid for everything.

    Unlike Java where new Integer(1) != new Integer(1) or JS where "" == 0, Rust requires you to specify when equality comparisons can be made, and requires you to write out the implementation (or use the derive for a simple, common implementation).

    Unlike C# where record class Secret(String Value); will print out the secret into your logs when it inevitably gets logged, Rust requires you to specify when a type can be formatted into a string, and how it should be formatted.

    Just because a language does things one way doesn’t mean every language ever should do things that same way. If you want it to work like another language you like to use, use the language you like to use instead. Rust language designers made explicit decisions to not be the same as other languages because they wanted to solve problems they had with those languages. Those other languages are still usable though, and many solved the same problems in other ways (C#'s nullable reference types, Python’s type hints, TypeScript, C++'s concepts, etc).