3 ms·

What’s your complaint about the question mark operator?

bonzini 4y ago
It's not extensible (the `Try` trait is unstable) but this is being worked on, see https://github.com/rust-lang/rfcs/blob/master/text/3058-try-trait-v2.md https://github.com/rust-lang/rfcs/blob/master/text/3058-try-....
dgb23 4y ago
In of itself it seems like a very nice feature. However it represents something that I don't like, which is trading language surface complexity and readability for programmer convenience. It is not something that gives you more power, just something that makes code a bit easier to write. Also there was seemingly not that much push-back against the feature which makes me a bit uneasy. Not sure why that is to be honest. I don't want to start a discussion about the question mark operator specifically. That's not important to me. What I like to gauge is the general culture around the language itself and the community around it. Half devil's advocate, half uncertainty driven.
- Fiahil 4y ago
  > However it represents something that I don't like, which is trading language surface complexity and readability for programmer convenience. In this case it's a welcomed convenience. Have you used `thiserror` and `anyhow` crates ? They may alter your judgement on that point.
- bigbillheck 4y ago
  > It is not something that gives you more power, just something that makes code a bit easier to write. Who needs a for loop when you have while?
  - dgb23 4y ago
    For and while have different semantics. For is not just sugar for a while loop, it means something more specific and restricted than a general while.
    - jeffparsons 4y ago
      For _is_ "just sugar for a while loop". In fact, here's the Rust documentation detailing what a `for` loop "de-sugars" down to: http://doc.rust-lang.org/nightly/std/iter/#for-loops-and-intoiterator http://doc.rust-lang.org/nightly/std/iter/#for-loops-and-int... > it means something more specific and restricted than a general while Sure, but that's still sugar. That's what sugar is. Want to know something really crazy? In Rust, the `if` keyword is also just syntactic sugar over `match`. Still finding bits of grey matter on the walls from when I learned that one.
  - jeffparsons 4y ago
    `while`? That's just sugar on top of `loop` that automatically inserts an `if` and a `break` for you. Don't be lazy, spell it out. (Although, in Rust, `if` is also actually just sugar over `match`, so, uh...)
- ntoskrnl 4y ago
  > trading language surface complexity and readability for programmer convenience I would say the question mark improves readability, compared to having to check/return error codes by hand after every function call. To your more general point, the language is pretty much established and syntax features are added very rarely. I think one more feature, let guards, is coming down the pipe soon, but other than that I wouldn't be surprised if the surface syntax never changes again.
  - mmarq 4y ago
    > I would say the question mark improves readability, compared to having to check/return error codes by hand after every function call. Which is one of my complaints about Go. result, err = doSomething(); if err != nil { ... } result, err = doSomething2(); if err != nil { ... }

It's not extensible (the `Try` trait is unstable) but this is being worked on, see https://github.com/rust-lang/rfcs/blob/master/text/3058-try-trait-v2.md https://github.com/rust-lang/rfcs/blob/master/text/3058-try-....

dgb23 4y ago

In of itself it seems like a very nice feature. However it represents something that I don't like, which is trading language surface complexity and readability for programmer convenience. It is not something that gives you more power, just something that makes code a bit easier to write. Also there was seemingly not that much push-back against the feature which makes me a bit uneasy. Not sure why that is to be honest. I don't want to start a discussion about the question mark operator specifically. That's not important to me. What I like to gauge is the general culture around the language itself and the community around it. Half devil's advocate, half uncertainty driven.

Fiahil 4y ago
> However it represents something that I don't like, which is trading language surface complexity and readability for programmer convenience. In this case it's a welcomed convenience. Have you used `thiserror` and `anyhow` crates ? They may alter your judgement on that point.
bigbillheck 4y ago
> It is not something that gives you more power, just something that makes code a bit easier to write. Who needs a for loop when you have while?
- dgb23 4y ago
  For and while have different semantics. For is not just sugar for a while loop, it means something more specific and restricted than a general while.
  - jeffparsons 4y ago
    For _is_ "just sugar for a while loop". In fact, here's the Rust documentation detailing what a `for` loop "de-sugars" down to: http://doc.rust-lang.org/nightly/std/iter/#for-loops-and-intoiterator http://doc.rust-lang.org/nightly/std/iter/#for-loops-and-int... > it means something more specific and restricted than a general while Sure, but that's still sugar. That's what sugar is. Want to know something really crazy? In Rust, the `if` keyword is also just syntactic sugar over `match`. Still finding bits of grey matter on the walls from when I learned that one.
- jeffparsons 4y ago
  `while`? That's just sugar on top of `loop` that automatically inserts an `if` and a `break` for you. Don't be lazy, spell it out. (Although, in Rust, `if` is also actually just sugar over `match`, so, uh...)
ntoskrnl 4y ago
> trading language surface complexity and readability for programmer convenience I would say the question mark improves readability, compared to having to check/return error codes by hand after every function call. To your more general point, the language is pretty much established and syntax features are added very rarely. I think one more feature, let guards, is coming down the pipe soon, but other than that I wouldn't be surprised if the surface syntax never changes again.
- mmarq 4y ago
  > I would say the question mark improves readability, compared to having to check/return error codes by hand after every function call. Which is one of my complaints about Go. result, err = doSomething(); if err != nil { ... } result, err = doSomething2(); if err != nil { ... }