4 ms·

Rust has no reasonable specification yet although it is being worked on.

bluejekyll 7y ago
I would say that rust doesn’t have a formal specification, what it does have is close to or better than many languages “specs” with the “Rust Reference”: https://doc.rust-lang.org/stable/reference/ https://doc.rust-lang.org/stable/reference/ It really depends on how strictly you define the term specification. The Rust Reference is not required to be accurate. Though many other language compilers/implementations don’t fully implement their respective specs so, :shrug:.
- mjw1007 7y ago
  The Rust Reference is very far from being complete, or even correct in what it does cover. If I have a question whose answer isn't obvious, it's far more likely that I have to go trawling around in RFCs than that there's an answer in the reference. I think most languages of a similar age (eg Go, Swift) are doing better.
  - littlestymaar 7y ago
    Rust is younger than Go (released in 2015 vs 2012) and way more ambitious, especially Rust 1.0 was released as kind of an MVP and many things have changed since then, which made the maintenance of such a reference an issue. The pace of change is slowing nowadays (that's especially visible if you look new and accepted RFCs), so I hope the reference will catch up eventually.
- clarus 7y ago
  There are some people studying Rust with formal verification. For example in this paper https://plv.mpi-sws.org/rustbelt/rbrlx/paper.pdf https://plv.mpi-sws.org/rustbelt/rbrlx/paper.pdf However I do not know if the whole language is covered or only a core.
  - sanxiyn 7y ago
    The big gap with RustBelt is that it does not cover traits. This actually does matter: some bugs were missed because they interact with traits.
cbmuser 7y ago
Which is the main reason why no usable alternative implementations exist yet and why Rust hasn't found its way to more low-level software projects like the Linux plumberland yet. Rust dearly needs a stable specification, it is the main blocker why the language hasn't been more widely adopted.
- galangalalgol 7y ago
  Rust has LTS like releases based on years, but the last one didnt have async await so everyone just kept tracking. I think the nexts LTS type release may snag some people and slow stuff down. Cargo should handle that fine, but not sure about maintainers. I cant get cargo in my day job, just the rustc 1.3x shipped with rhel, so I'm already standing still. Rhel's version migh make a good defacto lts in the absence of cargo, but the thin std lib makes that hard, and random old rustc versions sometimes don't play nice with every crate.
  - pietroalbini 7y ago
    Rust doesn't have LTS releases. Editions are both a way to market the new features introduced in the past years as a "bundle" to outside users, and a way for us to introduce some breaking changes for the users opting into the new edition. The release an edition is stabilized in (1.31 for Rust 2018) does not get any special treatment from the Rust team though, and that includes no LTS support (for example we won't backport bug fixes, even security ones).
    - galangalalgol 7y ago
      Yikes! I had no idea. It takes my company years sometimes to approve a new point release of software. Rhel subscription was my backdoor to get rust at work. I knew I'd never get a cargo access or a mirror approved, but i thought some day I'd push for an lts release. I don't see my company ever doing sw approval and transfer to our development network faster than once a year.
      - pietroalbini 7y ago

I would say that rust doesn’t have a formal specification, what it does have is close to or better than many languages “specs” with the “Rust Reference”: https://doc.rust-lang.org/stable/reference/ https://doc.rust-lang.org/stable/reference/ It really depends on how strictly you define the term specification. The Rust Reference is not required to be accurate. Though many other language compilers/implementations don’t fully implement their respective specs so, :shrug:.

mjw1007 7y ago
The Rust Reference is very far from being complete, or even correct in what it does cover. If I have a question whose answer isn't obvious, it's far more likely that I have to go trawling around in RFCs than that there's an answer in the reference. I think most languages of a similar age (eg Go, Swift) are doing better.
- littlestymaar 7y ago
  Rust is younger than Go (released in 2015 vs 2012) and way more ambitious, especially Rust 1.0 was released as kind of an MVP and many things have changed since then, which made the maintenance of such a reference an issue. The pace of change is slowing nowadays (that's especially visible if you look new and accepted RFCs), so I hope the reference will catch up eventually.
clarus 7y ago
There are some people studying Rust with formal verification. For example in this paper https://plv.mpi-sws.org/rustbelt/rbrlx/paper.pdf https://plv.mpi-sws.org/rustbelt/rbrlx/paper.pdf However I do not know if the whole language is covered or only a core.
- sanxiyn 7y ago
  The big gap with RustBelt is that it does not cover traits. This actually does matter: some bugs were missed because they interact with traits.

cbmuser 7y ago

Which is the main reason why no usable alternative implementations exist yet and why Rust hasn't found its way to more low-level software projects like the Linux plumberland yet. Rust dearly needs a stable specification, it is the main blocker why the language hasn't been more widely adopted.

galangalalgol 7y ago
Rust has LTS like releases based on years, but the last one didnt have async await so everyone just kept tracking. I think the nexts LTS type release may snag some people and slow stuff down. Cargo should handle that fine, but not sure about maintainers. I cant get cargo in my day job, just the rustc 1.3x shipped with rhel, so I'm already standing still. Rhel's version migh make a good defacto lts in the absence of cargo, but the thin std lib makes that hard, and random old rustc versions sometimes don't play nice with every crate.
- pietroalbini 7y ago
  Rust doesn't have LTS releases. Editions are both a way to market the new features introduced in the past years as a "bundle" to outside users, and a way for us to introduce some breaking changes for the users opting into the new edition. The release an edition is stabilized in (1.31 for Rust 2018) does not get any special treatment from the Rust team though, and that includes no LTS support (for example we won't backport bug fixes, even security ones).
  - galangalalgol 7y ago
    Yikes! I had no idea. It takes my company years sometimes to approve a new point release of software. Rhel subscription was my backdoor to get rust at work. I knew I'd never get a cargo access or a mirror approved, but i thought some day I'd push for an lts release. I don't see my company ever doing sw approval and transfer to our development network faster than once a year.
    - pietroalbini 7y ago